instruction stringlengths 24 29.9k |
|---|
I am taking a course on security next month. As the concepts of SSL/TSL are bit hard. I am looking for a nice way of presenting it to my students. They are Compsci undergrads.
It would be nice to have a reaal life one on its working. I think people here could help me in this
|
I'm a pentest newbie. Recently I've learned about sniffing in LANs. From the books and internet resources I'm studying, the sniffing (or packet capture) is always done on either Wired LANs (Ethernet 802.3) or Wireless Lans (Wifi 802.11).
But what about others like cell phone communication, SMS etc. They also use wirele... |
A point that keeps getting mentioned in the SOPA debate is that the DNS blocking it prescribes will cause security problems. Can somebody explain in simple terms just exactly how SOPA threatens Internet security?
|
As I understand, ARP spoofing can only be done on the LAN-side of the router?
DNS spoofing, can that be done either side of the router?
In order to do DNS spoofing, do you need to perform ARP spoofing first?
|
Are there any things which the user can do, on their own machine, to protect against DNS spoofing? I was just thinking when I was at the airport last and I wanted to check my email I used a hotspot access point, paid for the access using my paypal and that could probably have been intercepted. What could I have done fr... |
I have a session token that's stored in a browser cookie client side. The cookie is already available for scripting and it's used to validate XHR through Javascript. For a particular page I'm using an iFrame to upload data to the server. Would there be any issues, beyond what I'm already exposed to, by including the ... |
Our startup has something like 100 usernames and passwords to keep track of, and we can't keep track of all of them. Would putting all of them in a Google spreadsheet shared amongst ourselves be a bad idea? It feels like a security problem, but I can't articulate why I think that.
|
What is a good resource for wordlists used in auditing passwords in non english languages. I have extensive wordlists in English ranging to several GB's, but can't find similar resources for other languages.
|
In my uploading user's avatar scenario, I change users picture extension to jpg.
Is this making the browsers to act differently? Is it prone to error for browsers when they read users avatar?
Moreover, does it make my web app more secure when an attacker upload a php file?
|
I was tasked to implement some sort of password-based encoding/decoding in an android app by my non-tech SO. He also showed me this list of android security providers. Naturally, He chose the one with the most acronyms and highest numbers (PBEWITHSHA256AND256BITAES-CBC-BC) to go with.
How do I explain to him (in layman... |
Am I right in thinking that VPN doesn't protect until you're out onto the external network (assuming you're connecting from within an internal network)? Or does VPN provide confidentiality from the user's machine because the encryption is done using the client software?
Im trying to understand if I was on part of an in... |
Why open-source is better in plain words?
Yesterday I had a talk at a DIY bicycle workshop. There is a PC (running XP) that main application is checking emails (nothing really serious).
I found it excetpionally hard to explain why open-source security standards are better, that security-thru-obscurity is not the right ... |
1a) What software can I use to generate my own rainbow tables, preferably software that can utilize CUDA or ATI Stream?
One of the reasons I want to make my own, is that I want to use a specific charset/alphabet.
1b) If I want to make a rainbow table for a custom/rare hash algorithm, do I have to write my own software?... |
My company uses Websense, when someone goes to youtube by directly hitting url from browser
it says it's blocked due to category :Entertainment.
When someone searches for a video in google and clicks it , they can see the video , how is this possible?
If someone could say how its possible, i could make a work-around a... |
I am learning SQL injection on a vulnerable web app. I scanned it with w3af. It showed many vulnerabilities. One of them is:
SQL injection in a Microsoft SQL database was found at: "http://www.example.com/Login.aspx?CurrentPage=Login", using HTTP method POST. The sent post-data was: "...ctl00$cphMain$txtUserName=d'z"0... |
I should apologize first- this post could seem a lot to ask for, but I am starting to go around in circles. I am interested in securing my laptop for when I use public wireless hotspots, as I am a business traveler and frequent airports a lot. I have to do a large amount of online banking, visiting secure https website... |
i am planning to implement one WIFI security system , in which one can lock or unlock door remotely.
As i have serched over internet and i came across
lockitron and schlage
Now what i want to know is
1) the physical setup required to implement this project.
I mean what hardware i will be needing to implement it ?
2) ... |
The hosts OS might be Windows 7 and its firewall activated and the visualization is done by Virtual Box , but I think these details are less important.
This question might be related in some way to this which focuses on bridged mode, but my focus here is on using NAT.
Edit:
Can malicious sites one visits from inside th... |
Are there any security risks in using a static IV if I generate a new random KEY for each set of data to encrypt?
If I understand correctly what the purpose of the IV is in Cipher-block chaining mode of operation, there is no issue in doing things like this. Am I missing something?
If it helps, I am talking about somet... |
I can use the system function in PHP to get the MAC address of site visitors (probably most of you know). Why do we use IP addresss to check whether someone is stealing a cookie or not?
Does the system function have more overhead, or is it still insecure when we don't send any parameter to the function?
I know there ar... |
I use the school computer, which I bought from school, administered by the IT-department. I opened a port to my computer when I stumbled upon this:
It points to my computer IP. (I have a static IP to my router.) The contract says the IT-department isn't allowed to enter our computers via a backdoor, but I already cau... |
How would people use MySQL in C#, or really any other managed application? Couldn't someone simply decompile the application and find out the password/etc. for the database?
|
If I were to offer two networks (one for trusted users and one to visitors) on one physical access point, is this dangerous because a visitor could compromise the trusted network across via the physical access point where both sets of wireless data propagate through?
|
Looking at a certificate for a web-site (in Windows/Google Chrome) I see it lists the following fields
Version
Serial number
Signature algorithm
Issuer
Valid from
Valid to
Subject
Public Key
Basic Constraints
Certificate Policies
CRL Distribution Points
Enhanced Key Usage
Key Usage
Subject Alternative name
Authority I... |
I think the title says everything,
how secure is it to use apt-get in a network with an attacker who injects his own packets and blocks the original packets (man in the middle).
|
How would you analyze an image to find out if there are scripts or possible malware embedded in it? What tools / methods to use?
|
We upload users avatar with their primary key name. avatars name are 1.jpg,2.jpg,3.jpg,... according to their primary key.
We implemented this to omit avatar field from database, instead with use their primary key to access their photos.
Is it vulnerable or I'm just too sensitive about it?
|
We would like to install a Web App written in C#/.NET4 on client servers, not ours. I would like to know what are the best security practices to implement for avoid the following:
Authority stealing.
Read files with sensitive data.
Software tweaking.
Any security issues.
I heard someone talking of encrypting the Web.... |
On the last step of Kerberos, the client sends the target server a ticket and an authenticator. One of the authenticator's parts is a timestamp. The timestamp is said to prevent replay attacks, as the server can verify a message is fresh, and that it has only been sent once (using a cache). This is all clear. What I do... |
Something on the wikipedia page regarding captive portals have confused me:
http://en.wikipedia.org/wiki/Captive_portal
When a client requests a website, DNS is queried by the browser. The
firewall will make sure that only the DNS server(s) provided by DHCP
can be used by unauthenticated clients (or, alternatively... |
Here's an example PKI setup:
* Root CA (offline)
* Issuing CA
* Client 1
* Client 2
I'd like to specify a CRL distribution point for CRLs generated by Root CA, and an OCSP URL for Issuing CA. So information about revoked client certificates is available only via OCSP. Information about a revoked Issuing CA (... |
Truecrypt can easily automount if your drive is not entirely encrypted and your data is a standard file. However I have my entire removable storage encrypted and so to the OS, it is seen as an unformated disk. Is there anyway to automount said drive?
|
For companies that needs to monitor computer usage by employees, what systems are usually set up to do so (monitoring software, hardware, etc.)?
What are the financial costs involved in setting up such a system?
|
I was Googling one of my domains (hosted on shared hosting) and found a webpage where it was list as Hacked Site, the list belonging to a certain national hacking group (the country they claim to belong is notorious for lot of international troubles, but the country, as such, has no accords in hacking World).
Only the... |
I have a spare computer lying around at my house, so I decided to turn it into a honeypot. So far, I have installed Windows XP (no service pack) on it and have set up rules on my router to forward (some) ports to the honeypot. Since my router doesn't support DMZ, I have to manually create rules. Currently, I forward TC... |
Obviously, if auto-logon is enabled, anyone who can gain physical access to the PC can use the PC. That's not the question.
The question is, when I enable auto-logon for my Windows 7 box, will there be any additional security problems?
Does the setting "Users must enter a user name and password to use this computer." a... |
A application use the debug as boolean to prefill login, password for authentication.
The code is something like that :
if (ContantsFile.CUSTOM_DEBUG_FLAG) //static final
{
//disable access control ==> admin mode (admin section are now visible for anybody)
}
The application is coded in JAVA.
And the constants.class is... |
I'm doing some testing on my web app with Tamper Data. I've had success with Tamper Data in the past for normal HTTP post requests, but in this particular case I want to modify a post request that that has the content-type set to multipart/form-encoding.
Tamper Data shows this request as one big blog of messy escaped-n... |
I'm auditing a piece of Java code that might be vulnerable to header injection :
String headerValue =request.getParameter("headerVal");
//escaping CRLF
headerValue = headerValue.replace("\n", "");
headerValue = headerValue.replace("\r", "");
response.addHeader("myheader",redirection);
This code is present directly in... |
In linux every user can create symlinks, but in Windows I need an admin command line, or mklink fails. Why is that?
|
I've downloaded a part of .htaccess to prevent from using base64_encode or <script> or _REQUEST within URL. Is this secure enough to help me out for partial security, or is it just a waste of time and resources?
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+c... |
I received a spam abuse few days ago on my server.
As a precaution, I blocked the SMTP port and started an investigation.
I found a running Perl process. The script it was using was deleted but I found its contents in /proc/PID/fd/3. Here's its md5:
server:~# md5sum spam_scipt
c97b6d65fe2e928f190ca4a8cf23747c spam_sci... |
I have accounts on several third party sites - Bitbucket, Bluehost, etc.
From what I've gathered, it is common practice to use one key pair for all [id_rsa, id_rsa.pub], but only to give out the public key
Is that the correct usage, or is it better to generate a new pair for each site?
It would seem to me that thi... |
Is there a name for a system that is designed to be hacked into?
(Alternatively, there may be a different name for a system that is designed to look like it is hacked in to, but is actually just emulating?)
And is there a name for an executable that looks interesting to a hacker (for example decryptor.executable next t... |
I would like to buy a USB fingerprint scanner. I intend to use it to log in into my Windows computer, to secure RoboForm password manager, and generally to replace password entry with a quick finger sweep in as many places as possible.
What I'm asking here is not a shopping recommendation. Instead, I would like to kno... |
I would like to provide content when a hacker tries something like GET /../../../etc/passwd, but they may choose something else, other than passwd. I will install notification of when somebody does this, but in order to keep the hacker's attention in a fixed point for some time, I would like to have some fake data.
Doe... |
I looked at this question: What is the right way of storing database connection strings from the security point of view?
And I'm wondering specifically for connecting to a MySQL database with PDO, how can I be more secure?
I currently store my password in plain text in a .php file.
If storing outside the root is optim... |
Today we were robbed. A thief come to our home at night and stole some stuff including my brother's laptop.
I think that the right thing to do is to download a keylogger on my PC, just in case...
I want a free keylogger, which has GPS to locate the PC, I know professional thieves will not connect the PC to the internet... |
I am playing around with a test application which accepts JSON requests and response is also JSON. I am trying to do a CSRF for a transaction which accepts only JSON data with POST method in request. Application throws an error if URL is requested using get method (e.g. in <script src=).
Also for the attack to be meani... |
I have some links that contain hacking tool and whatnot and I want to pass them to a virus scanning service. The thing is that I don't want to download them to my pc and upload them to their service, but rather to have it scan the files remotely by just passing them the URLs. Do you know of any service with a simple wa... |
I would like to use a dropbox because it is easy and convenient.
But I want to encrypt the files with the public key of the intended recipient, so he will be the only one who can access the data in the file.
I have not found an easy mechanism to encrypt the data before it is stored in the dropbox.
Is there an easy wa... |
If I'm an administrator of a corporate network, I could use an HTTP proxy to examine outgoing connections to monitor what websites my employees are going to, and terminate connections based upon policy/content rules.
Or, I put an invisible bump-in-the-wire box at the gateway to examine traffic content and terminate con... |
What are recommenced books, videos and other resources for CEHv7. It seems as though not much is published on the new version of the cert just yet. Currently, I have read All In One CEH by Matt Walker. I plan on taking the test without attending the course as I tend to do better at self study.
|
I have an Android phone. When it's connected only to my carrier's 3G network I imagine it's reasonably secure against eavesdropping (although not invulnerable). However, at times due to lack of reception or other reasons, I may connect to a public Wifi network and use my phone that way.
It worries me though. If I use m... |
I'm curious if knowing the exact content of an encrypted message or several messages makes it theoretically any easier to discover the encryption key. Does this speed up a brute force attack in any way? Or provide some other means of discovering the key?
How would this concept apply to both symmetric encryption and asy... |
https://www.youtube.com/watch?v=Z7Wl2FW2TcA
What are the "Notary" servers regarding convergence? Who is maintaning the "Notary" servers?
Can someone please explain?
|
I have been reading some very interesting academic papers regarding the ability to search encrypted data without needing to actually decrypt the data. Doesn't this defeat the purpose of encryption in the first place? I can imagine language-specific "brute force" attacks in which I re-assemble the plain text from the ... |
I visit the airport, I pull out my laptop and connect to a network (no password needed).
I open up my browser and i am presented with a screen saying I need to pay to use the network. If I pay, I presume if I close my browser and then open it back up, it wouldnt ask me to pay twice.
How does the browser know when the u... |
I've been reading a lot about one-time-use online credit card numbers (e.g. https://www.discover.com/credit-cards/member-benefits/security/create-online-account-number.html#) but I have to admit that I'm actually more worried about small businesses getting exploited (e.g. http://arstechnica.com/business/news/2011/12/ho... |
After reading this question about how for-pay wifi routers identify specific devices it got me thinking about what a secure alternative might be. I know that certain research has focused on identifying devices by their browser signature and by their hardware clock skew signature. The former can be defeated by changin... |
I was taking a look at someone's computer who had a virus. It called itself "Visa Antivirus Security 2012". It turned out to be ltd.exe. It would seemingly randomly block programs, it turns out it had infected the "open with" option for exe files. Renaming the exe then restoring the open-with references that contained ... |
I am looking for secure coding guidelines especially for mobile devices (Android and iOS). The languages I am interested in are Objective-C, JAVA and HTML5.
Would it be a good approach to use a "classic" security framework like the ESAPI for JAVA?
|
Is possible to protect files from being copied if you are the administrator of a machine? I heard that this behaviour is possible: one software developer sells his software in such a way. He installs it on every client's computer to prevent the software from working on other computers or to prevent it from being physic... |
In the app I'm writing I separated the user and main databases a long time ago for "security reasons". However its getting harder and harder to justify the overhead and the difficulty of managing such a setup.
For some quick detail this is a PHP web app. There are 2 separate mysqli connections, one for each database. E... |
If someone finds a vulnerability like buffer overflow in a program such as Google Chrome or Mozilla Firefox running on a linux machine, are there any chances that this vulnerability will persist on Mac OS X or Windows running same program.
|
Everyone knows the words used in Diceware passwords (all 6^5 = 7776 words are published) -- they're all common words.
Everyone seems to know that we're not supposed to use dictionary words for passwords because the "dictionary attack" can rapidly guess a single dictionary word.
So it seems reasonable to leap to the con... |
I want make my software more secure. I want prevent it from brute force attack. I know that a strong password is the best but I can not control it.
The algorithm must scale from a very small system with only some users to a very large system.
A captcha is not an option.
No real user should be blocked because there is ... |
Unfortunately our government filters the SSH protocol so now we can't connect to our Linux server.
They do the filtering by checking the header of each packet in the network layer (and not by just closing port). They also do away with VPN protocols.
Is there any alternative way to securely connect to a Linux server? ... |
The passwd/shadow files in a unix-like OS contain sensitive info such as a user's password. In addition those files aren't necessarily secured: with a live CD we can access those files on the hard drive and potentially gain access to the sensitive information.
My question is: is there anyway to make those two files mor... |
Our company wants to implement a service based on sniffing for security purposes, since we manage important information this requirement is imperative. The situation is as follows.
Everyone in the office uses a VPN for preventing external eavesdroppers to sniff in our network. Although, the company is looking forward t... |
I am interested in cost effective and creative ideas for detecting physical attacks against computer systems. This includes, but is not limited to Tamper Evident security measures.
Consider the following attack scenario:
An attacker would like to obtain data from a harddrive. The target machine is setup with Full D... |
Tripwire type intrusion detection systems supposedly protect your system from rootkits, by monitoring the checksums of important binaries for changes.
Let's say I have tripwire configured to run nightly and installed it on a fresh non-rootkitted system.
Then at noon today a skilled intruder installs a rootkit to my s... |
As a followup to "Tripwire - Is It Security Theater", I'm looking to get a better idea of what a rootkit is. To be more clear:
What is a kernel module?
What at high-level is the flow for how it's loaded, and why/what memory is of value?
Do linux kernels receive patches or have other defenses that prevent rootkits from... |
I installed Convergence on Firefox 9.0.1:
http://convergence.io/
but... after I installed/enabled it when I visit a HTTPS only-site there are many-many HTTP traffic to the notary servers. Why? shouldn't those connections be encrypted?? Can someone explain it to me please?
|
I'm creating custom certificates with CDP Definitions with the option of configuring several methods of accessing the CRL. My options are HTTP, LDAP, and FTP. What are best practices or should I say why pick one vs the other?
|
I asked a question earlier today on serverfault, but found out that there was also a security stack exchange. I had conflicting answers from there. The following is the link:
https://serverfault.com/questions/346609/dos-attack-simulation-vs-real-deal
One person states that there is no difference, whereas another has st... |
My objective is to learn and practice all the vulnerabilities and their exploitation on vulnerable OS.
|
I've see the PVS (passive vulnerability scanner) from Tenable Network Security.
I'm really interested in this kind of approach.
Anyone know if is there any FOSS solution to be used professionally in a company ?
P.S. I know that, from the point of view of functionality, is a sort of NIDS with pattern matching engine w... |
This is sort-of a follow-up to my previous question What fields in a suspicious certificate should I look at?
Chrome just presented the warning icon against the certificate presented by https://login.facebook.com (I always type the URL in) because it could not verify the CRL. For want of anything better to do, I downl... |
I'm trying to decode an X.509 certificate and have a question regarding the decoding of the extensions. In particular, the octet string corresponding to id-ce-keyUsage (OID 2.5.29.15) is as follows:
03020106
03 is the tag. A BIT STRING. 02 is the length. The value is 0106. Here's what http://www.itu.int/ITU-T/stud... |
I'm trying to monitor connections and actions made by administrators (or any user connecting) to a server through TSE (i'm simplifying).
I've heard about a software which can record a video of any TSE session (you can define framerate of the capture) started on a server (an Agent has to be installed on the target serve... |
Exactly what kind of information does a scammer need to scam someone money?
For example, if there's a website which wants me to provide my details, Exactly what kind of information can I divulge and guarantee that the scammer does not have the ability to scam me?
Basically, could I be scammed by a website who has my co... |
I want to exploit a stack based buffer overflow for education purposes.There is a typical function called with a parameter from main which is given as input from the program and a local buffer where the parameter is saved.Given an input such that nops+shellcode+address_shellcode i will exploit it.After debugging with g... |
I am looking to give some files to my accountant, who is not computer-savvy. I am going to put the files on a flash drive encrypted. I assume, accountant has no software other than standard Windows for decryption. I cannot rely on accountant being smart enough to download and install tools like truecrypt or 7-zip. I am... |
On a lot of tutorials on luks encryption, people say to override the partition with random data, so that data is not recoverable after encryption. I don't understand that. Will the random data be appended to the free space? Otherwise data would be lost, wouldn't it?
I've an unencrypted root partition and swap partition... |
Let's say you're using Windows 7.
For storing Bitcoin on your computer ... is downloading a fresh copy of linux (say Ubuntu), burning it into a CD, booting from it ... safe from trojans?
Are there trojans "in the wild" that would be able to "jump hosts" from a Windows machine via the BIOS into the new linux OS, running... |
If I am a remote user, connecting to my firm from home, using IPSec VPN tunnel or through SSL, and an attacker is intercepting all of my traffic, will he be able to watch my VPN session on the clear (he is there before the IKE phases and all of the exchanges). And will it differ on SSL and IPSec?
[MY Firm]--->[My Firm'... |
Is it possible to sniff or record and process GSM 3G signals (from some reciever) given that there is no other signals interrupting etc (the most comfortable conditions)
Update (with some supporting material )
http://events.ccc.de/congress/2010/Fahrplan/events/4208.en.html
|
All of our HP PCs come with this software pre-installed, I'm a bit inclined to outright remove it because:
Credential manager stores passwords by default (this has lead to user confusion, plus storing passwords drives me crazy from a security standpoint, especially when I don't know how these passwords are secured at ... |
I've heard that even if you have a Word document encrpyted (just using the built in Word encryption tools) and are editing it, it can still leave behind remnants of a file on the local computer in either hidden files or a cache somewhere. I'm not sure if that's even true or not, just something i thought I heard somewhe... |
We have an application that sends mail in bulk, via a mail provider (Mailjet). Our clients are professional organizations, and they send important mails about meetings and stuff like that, to about 10 to a few hundred contacts at once. Our mail provider has delaying rules, which means that if we ask them to send 1000 m... |
I made an application which uses ftp so windows shows windows security alert windows firewall has blocked some features of this program message for every new version of my application any idea how to fix this so user does not have to press unblock for every new build of my application?
I publish my application using v... |
IMHO the 'screen dimming'-and-displaying-of-warning-window feature (?) in Windows is extremely annoying, since I routinely run software that does require the permission to modify a lot of things. I must confess I'm not familiar with the underlying mechanisms of User Account Notification. Is there any benefit to leaving... |
The three classes that we all know and love:
Something you know.
Something you have.
Something you are.
I've also seen references to "somewhere you are". Is this really a fourth factor? How many factors are there?
At some point some of the factors might start to resemble others such as the blurring of the "something... |
I recently had a chat with a cracker and he told me that he can get past uri regexp checking.
I'm checking if the path_info matches my regexp and after that I match that to my routing table. If there is no routing for that path i redirect to a 404 page.
I have some little code here and I was wondering whehter someone c... |
Is that called a 'round' every time you move your mouse when creating a new volume? I'm talking about the screen with the random numbers during the volume creation process. What is the purpose of doing the random movement?
I saw Lastpass is now doing '100,000 rounds', I'm not sure what that means exactly.
Brand new to ... |
I would assume that A/V products would need to employ the same kinds of techniques used by the software they are trying to cleanse to ensure that they can continue to run in such hostile environments. However, A/V products are not exactly the most stealthy -- you can find evidence of them all over a Windows machine.
W... |
I've read the Wikipedia articles on SIPRNet and NIPRNet (which are pretty light on details) and they are supposed to be considered separate. At the network level, are they technologically incompatible or is there a high-level of human involvement to keep them unlinked and essentially airgapped?
Does SIPRNet run on its... |
I stumbled upon something called "scrypt" which claims to add fixed time/space complexity requirements into password-based key derivation.
Quoting from their page:
A simple password-based encryption utility is available as a demonstration of the scrypt key derivation function. On modern hardware and with default parame... |
Can anyone explain what is DNS zone transfer attack or give any link, paper?
I have already googled, but could not find anything meaningful.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.