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I configured my server to encrypt user passwords using 500,000 rounds of SHA-512.
The question is, how does the standard AES-128-CBC encrypted SSH private key stack up to that, provided the same (or similar length) password/passphrase is used? This must be a human-typeable passphrase, of course, and the lack of entrop... |
In contrast to digital cryptographic algorithms and protocols where many qualified high-IQ individuals dig into the details and specifics, physical tamper resistance for low-tech packages is not pentested as much.
There are some folks out there who do it for money, though, but their results aren't easily available. The... |
I've created a test site in order to learn about SQLi and then protect against it. I may be misunderstanding how it is supposed to behave but at present I'm not getting the results I expect.
The page:
<!DOCTYPE html>
<html><body>
<h1>SQL Injection Test Site</h1>
<h2>Login Form</h2>
<form action="" method="post">
Use... |
I just want to know better ways to protect source code from theft on Windows by Removable Devices like CD,Pendrive.
Here is what I know:
Windows Disk Encryption: Pretty nice to protect from offline attacks but when you copy code from encrypted drive to your pen drive windows automatically stores decrypted copy. ( Well... |
So at my business our receipt printer randomly printed some questionable looking data.
I looked into scanproxy.net and it's clearly not something legitimate.
Can anyone give me a better idea of what's happening here?
GET http://www.scanproxy.net:80/p-900.htm
1 HTTP/1.0
Content-Type: text/html
Proxy-Connection: keep-al... |
I'd like to track and understand if CORS/cross site requests are hitting my website, and if they are succeeding or failing.
My goal is to understand if clients are following our documentation correctly, and to detect attempts at hacking our site from a 3rd party.
I don't know if there is any value in reporting separate... |
The answer suggested in the 'duplicate' is about a different issue. But since my original wording of the question seems to have not been clear - here's a second attempt:
Is there any danger of any of my computer's files being read or changed (mainly - infected by malware) in the following scenario:
I have file sharing... |
I'm looking for a way of securely having passwords for different pages. Say I generate this password:
ild23rfsfdfg%*#fArg34t34657%537@asd7oak2094^*q2k2k@Kk3j4tn453Q5#
Then, for each site, I change a single character. It's a single, random position with a random character shift. Isn't it almost as secure as having a st... |
I have been messing around with Cain and Able and used APR on another computer (also mine) to get a hashed version of my username and password for my yahoo e-mail account, but I seem to be lost as to what to do next. I know that I need to crack the encryption on the password, but when I right-click on the hash and clic... |
Regarding to trusted sites like YouTube, should I trust other videos when embedded to Facebook, usually, when user shares a link a thumbnail image will be created and previewed, then, we need only to click on Play icon (Or the thumbnail) to play the image.
Is there any risk behind that? Considering an attacker can bypa... |
How secure is the encryption offered by ubuntu (using the disk utility)? What algorithm is used underneath it?
If someone could at least provide a link to some documentation or article regarding that I would be very grateful.
Reference:
|
I've setup a test environment for running some SQL Injection against my code and learning how to defend against it. I can bypass the login form using the following in the password field:
' OR username = 'admin
Which gives me the query:
SELECT * FROM customer_data WHERE username = '' AND password = '' OR username = 'ad... |
I have a web server supporting SSL 3 and TLS protocols, the following are the supported cipher suites:
TLS_RSA_WITH_RC4_128_MD5
TLS_RSA_WITH_RC4_128_SHA
TLS_RSA_WITH_3DES_EDE_CBC_SHA
How can I check if the server supports NULL cipher ?
|
I have encrypted part of my web.config file using the Data Protection API.
Now, my question is, what does a hacker need in order to decrypt the web.config file?
Does he require physical access to the machine in order to decrypt it? Or can he decrypt it from a remote location?
|
Recently, an increasing number of people have started advising moving away from FileZilla. However, the only reason I can see for this is that FileZilla stores the connection information in a completely unencrypted form, but as Mozilla says - surely it is the job of the operating system to protect the configuration fi... |
I'm going to be hosting one of my websites on a VPS soon and I want to make it as secure as possible. Only I will need access to the VPS, and I can't see that changing in the near future. Because it is an eCommerce website, I will be purchasing an SSL certificate anyway, and I'll also have SSH access, so I'm not sure w... |
I am trying to find out how the TPM performs an integrity measurement on a system. It is well-documented in the TPM specification how it seals the data it has measured in the PCRs and how it is updated. But that which I can't find explained is how the TPM actually performs the integrity measurements that it is sealing ... |
Could entering sensitive keyboard input in public places with camera systems equipped with a robust AI possibly leak keystrokes via eye-tracking technology -- assuming the typist is using the hunt/peck method? This would assume the system uses some kind of spacial guess-work, creating a virtual map of the keyboard by ... |
I have to develop an application which uses another application for generating a CSR. After generating the CSR I have to provide this CSR along with a SHA256 hash of the public key to a CA. The problem is the application which generates the CSR doesn't generate the hash.
How do I generate the hashcode?
Can I create a k... |
A client has asked me to help them out with their WAF processes. Currently they have a few critical web applications being protected by a couple of WAFs. I have managed to get the WAFs tuned and ready for production. The company is fairly large and is expanding. Thus, I want to tackle the manageability of their web app... |
A researcher recently reported an issue in a site about using script on a 3rd party site to discover if a user is an admin.
Here's the scenario:
Main site is target.example
Attacker site is evil.example
target.example has SSL and HSTS and redirects all http traffic to https using a 301 redirect
the session cookie on ... |
The title says it all; I'm just serving data to coworkers as a courtesy via a series of single-page apps that I basically consolidated under Flask, serving Jinja templates. Presently, I have Apache running, and I just drop static HTML files in the path. But this was before employing Flask or a template engine and I'm... |
In the AWS ELB, I have uploaded a cert and only selected "RC4-MD5" + "RC4-SHA" as the ciphers and scored A in the ssltest [1]
If I using the default ELB setting, I can only score a C
Since I am not doing a PCI compliant site, so by using only the above two ciphers, is it enough for most purpose? (by enough I mean wide ... |
This may seem like a slightly esoteric question but, I am wondering if it possible to achieve a result summary in Nessus where the Total is 0 for a windows server? Things that have no risk factors like, "Host Fully Qualified Domain Name (FQDN) Resolution", "Additional DNS Hostnames", "OS Identification", etc...
|
My goal is to make a certificate's thumbprint "easier" to verify, and not reduce security in doing so.
Given that the RSA-based Bitcoin technology has a concept called a "Vanity address" where the random keys are regenerated over and over again until the hash has user-defined leading bits (the content and length of bit... |
I am looking for respected resources that state guidelines on how to design my network from scratch in a secure way, including different positioning scenarios for different network/security appliances like "when to create Vlans", "traffic directions", etc.
As per my knowledge, security should be built in and not to be ... |
I am building a PHP web application, that needs enhanced security, due to the fact that it contains very sensitive information (in a database).
I think that I want to use self-signed SSL certificates that will correspond to each user and store them one level above the web root folder (for simplicity's sake /var/www/ce... |
I saved a pst file on a CD. It contains a lot of email that was sent to me using a digital signature.
I am now in a lawsuit and need to print out those emails but no longer have access to my digital certificate or the other persons digital certificate.
Is there a way to unencrypt those emails without.
I think they wer... |
I am trying to proxy a mobile app (with Fiddler), which sends a client certificate to the server it connects to. I would think that capturing traffic with Tcpdump, retrieving the client certificate and using it with fiddler would be enough to bypass this.
However, when I capture packets using Tcpdump without a proxy, I... |
We have a web application linked to a database. The database is secured but contains unmasked confidential numbers. Can a normal administrator who can access the application, access those numbers in the database?
Note that there is no tools in the application that generates the numbers.
|
On a "forgot my password" page, is appropriate when user doesn't have an account to display the message "this account doesn't exist"? Or in the interest of security, should I display a success message ("you received an email with a reset password process") even if no email was sent?
|
We are connecting to Oracle using korn shell scripts, which use sqlplus to connect to Oracle. The Oracle database is on the same Solaris box. Currently, we are storing the Oracle user id and password (plain text) in a file in the .ssh folder of the connecting user, with 400 permission bits.
The DBAs are objecting to ... |
We're trying to determine if pushing data through a firewall is more safe than pulling it. The data will be from SSIS to SSIS through the firewall. An advisor here has suggested that pushing the data through the firewall is safer than allowing an external connection in to pull the data out.
Is this so ?
|
Consider if I have got a mail from a colleague on my GMail, and it has got some images or attachments in it. Gmail asks for "Show Images" option to explore images.
My query is that how can we get to know that these images or attachments are not for tracking our IP from websites like ReadNotify.
Is something to be not... |
I have read many Q&As here on IT Security about password hashing and salting.
I am building a simple registration form for our community website which will be used by our members to create their accounts. I am seriously debating the idea of asking users a security question that will require a single word answer and th... |
First off, this is in addition to using SSL! I am building a web application that receives encrypted data from a server. The data is to be decrypted client-side. I've read enough posts here to see that security implemented with JavaScript is hardly security at all, so I'm looking for an alternative to JavaScript base... |
Is there any mechanism in SSL/TLS which allows a certificate to be bound to a device? Example:
There is a client who talks to a server, and during SSL/TLS setup, there is mutual authentication. The server verifies that the client presented a certificate which is valid (Expiration date, CRL/OCSP, etc.) and has whate... |
In Unix crypt using SHA-256 and SHA-512 the author, Ulrich Drepper, introduces the SALT string as the following (highlight by me):
For the SHA-based methods the SALT string can be a simple string of
which up to 16 characters are used.
What is the rationale calling this string a simple string? What does it mean? Wh... |
What is the exact number of rounds employed by the MD5 and SHA512 hashing algorithms?
According to various sources, the SHA512 hashing algorithm employs a total of 80 rounds (http://en.wikipedia.org/wiki/SHA2).
On the other hand, I am confused when it comes to the MD5 hashing algorithm. According to Wikipedia, MD5 emp... |
Does BitMessage provide key authentication? If so, then how? How would one can be sure that the public key belongs to the right person?
|
I have a computer which is virus infected. Can I use the same keyboard on both it and a "safe/clean" computer without fear?
Keyboards these days seem to come with built in software and thus must have a small amount of memory... right?
|
Signal (former RedPhone) provides end-to-end encryption for your calls, securing your conversations so that nobody can listen in.
But really, how is the probability that a voice conversation is wiretapped still?
And are the contact-details (like phone-nr) concealed to the provider too? Or can the provider build a dat... |
I've been reading about solitare and its weaknesses, and thinking about clever ways of hiding keys. It seems like you could encode an 52-bit AES key in the vertical orientation of cards in a deck (or 104-bit if it wouldn't be suspicious that you have cards flipped back-to-front).
What I'm wondering is, would it be safe... |
Let's assume I have an 18GB database that is backed up nightly by dumping the database and then encrypted using a modern algorithm such as AES-256. This database has a daily update of rate of approximately 5%.
The storage medium the backups are saved on support block level de-duplication. I'm interested in knowing how ... |
I came across this very alarming sounding thread which indicates a GPU with about half the compute capacity of the GPU currently powering the monitor I type this on is capable of 11.5k c/s.
I'm not sure what a c is in this jargon. Does it stand for "crack"?
Does this mean 11.5 thousand passwords tested per second? So ... |
I've recieved an e-mail from ubuntuforums.org a couple of hours ago:
[...] the attacker has gained access to read your username, email address and an encrypted copy of your password from the forum database.
If you have used this password and email address to authenticate at any other website, you are urged to reset th... |
For an average user (doing on-line payments, etc.), would it be useful to periodically conduct a OS re-installation of his computer to improve security? How often would that be and how much extra security would that be?
Obviously, if you have the almost same system as before (thus almost the same flaws), then you are a... |
After a few days reading up about salting and hashing passwords, I found an actual bit of code that tells how to do it. This is what I found:
$blowfish_salt = bin2hex(openssl_random_pseudo_bytes(22));
$hash = crypt($data, "$2a$12$".$blowfish_salt);
Is this a good way to do it?
|
As I understand it, salting and hashing passwords is the way to go. I also understand that to authenticate a salted and hashed password, the random salt needs to be saved. Does this mean that if I use the following code to process the password:
$blowfish_salt = bin2hex(openssl_random_pseudo_bytes(22));
$hash = cryp... |
About 6 days ago I purchased a new domain under .org TLD from a local registrar.
Few days later, I have received this strange message (which BTW fell to
Gmail spam bin), which looks like some kind of phishing to me.
Following is the e-mail contents (redacted the hashes in "unsubscribe"
links and my domain for "example.... |
What is the best way of forensically determining that spyware software has been installed on the phones without making any changes to the phone(s)?
I have Blackberry and iPhone 4 phones that are suspected of having spysuite software (CellSpyNow) installed on them. It is suspected that a former employee has installed... |
Are there any other security threats to a mobile device other then a rogue app?
I am trying to secure a set of business phones and tablets and while anti-virus applications are possible, I don't see viruses of any kind really a threat. Seems most likely someone would download a rogue app that would act as a trojan.
|
Fictitious scenario:
User accesses a restricted data (available online) identified by random string (supported by captcha to make brute-forcing more difficult).
So data is not protected by a user/password account, but each case info is identifiable and accessible to all who know such random, unique string.
What is more... |
Is there any tool to perform penetration/vulnerability testing on REST web services ?
|
Salts are supposed to be unique and randomly generated for each user when storing passwords. Is there a reason why we can't generate these salts with a cryptographic hash function using the username as the input?
It appears to me that these hashes would give the properties we desire, and we wouldn't have to use additio... |
A common occurance I've found when doing forensics on compromised websites is a pattern like this:
<span>Clean code here</span>
<!--0c0a22-->
... malware code here ...
<!--/0c0a22-->
<div>clean code resumes</div>
In particular, HTML code is delimited with <!--marker--> ... <!--/marker-->, PHP code with #marker# ... ... |
Considering the scenario where a Gmail session/login cookie is hijacked or stolen and it is discovered my means of Gmail last account activity,will changing my password immediately void the cookie or can the attacker still use the same cookie to authenticate?
I am assuming that this is the same for other sites as well ... |
I was using Burp Suite to do some security testing on a site and I noticed that when it detects ViewState it will automatically tell you whether it has MAC enabled.
I'm curious if anyone know of a programatic way to determine if MAC is enabled if you are crawling a site without actually attempting to modify the ViewS... |
I was wondering why a company should use a private DNS.
In comparison with a public DNS, which advantages does a private one have, and which issues can a public DNS create for a company?
I'm new at these concepts of networks security, so maybe this is a very basic question.
|
I'm working on an embedded system that will generate an SSL key the first time the system boots. I would like to avoid the problems discovered by Heninger et al. and Lenstra et al. where embedded systems with low entropy have a tendency to generate the same keys. My understanding is that Linux gets its entropy from the... |
I'm currently a web developer for a company with lots of different remote clients. There are lots of usernames and passwords that I need to know so that I can do my job. When I first started, I was able to obtain a good chuck of credentials by reading them off my boss's computer. I stored them on my computer, in 1Passw... |
I am using AES encryption to secure some sensitive data. For that i have to provide a certain key for encrypting and decrypting.
It's not safe to keep the key somewhere on the server. So instead of entering the key directly, I would like to convert the key and later convert it back again to it's original when entering... |
I have been a developer and now I am trying to look at XSS from the point of view of a developer. I was thinking of a particular case of reflected XSS . Let us say we have a vulnerable website and if an attacker can trick the users to click on a malicious link he can get their session tokens by using document.cookie
I... |
I have to create an application which generates a CSR. While generating a CSR we are required to fill in several details like CN, OU, etc. The problem is that the Certifying Authority to which I have to send my CSR wants 2 OU(Organizational Unit) Names. I googled a lot but couldn't find anything using either openssl or... |
Case in point, TrueCaller. I had logged into TC using a proxy twitter account. I am assuming that as part of the authentication process, an access_token must have been saved by TC.
If the hackers have this token, what can they be able to do with it?
Assuming that the hackers have gotten a hold of my database, what ca... |
I'm using an application linked to a database which holds confidential data (numbers). According to the developer, this data is encrypted. However, i can easily generate a report that will show the numbers in clear text. How can the application access and get this data if they're encrypted? And if the data is accessed ... |
We’ve all become so accustomed to using email in our daily personal and working lives that we really don’t give a whole lot of thought to it. It’s the fastest way to communicate with others in the course of the day, and the emails we send and receive – in general – never see the light of day again once they’ve been r... |
I have a server on which I keep an encrypted backup of some data. The server updates the backup once a day if the data has been changed and is physically accessible to many people. Further, I would like to have easy access to these backups. Given these considerations, where would be the best place to store the encrypti... |
Srlabs have recently published article stating that many SIM cards can be exploited using vulnerability in DES:
[...] While the option exists to use state-of-the-art AES or the somewhat
outdated 3DES algorithm for OTA, many (if not most) SIM cards still rely
on the 70s-era DES cipher. [...]
Apparently it will tak... |
Say I have a site that has a user registration process where, when a user enters an email address already in use, an error message is displayed telling them that. This seems like a easy way to a malicious user to enumerate users.
Would adding CAPTCHA to the registration process be enough to prevent user enumeration?
|
I was reading about DNS security, and readed about Zone Transfer and how can be used to retrieve host information of a network, so not allowing Zone Tranfer from external sources will be the solution for that, so, is there other way for an attacker to obtain that info if the Zone Tranfer is not allowed??
|
There are a variety of other questions that address elements of this security issue, but none that seem (to a non-expert) to address the substantial core of the issues raised in this article:
Tinder's privacy breach lasted much longer than the company claimed
From a mobile perspective, what are the correct steps the ... |
Say, I have a website where users are required to login to access certain functionality. Once they are logged in, they are issued an authentication cookie. Some of the pages on the authenticated portion of the website use a secure connection, while others do not.
Is it possible for a man in the middle attack to steal t... |
I'm wondering about some of the semantics and security implications of using something like scrypt or bcrypt to "enhance" a password protecting a PGP private key. Essentially, I'm asking about the implications of using the scrypt of a password as the password for my PGP private key.
From my understanding, a PGP keypair... |
How can I configure NAT Settings when my router doesn't have advanced settings option.
|
I currently have a demo site setup where I load the login form over HTTP and then POST to a HTTPS URL. The aim is to demonstrate that this is not a secure method of handling the login.
I'm using Fiddler to alter the target for the HTML form to a page of my own. I'm trying to capture the POST data but then forward the u... |
Is it possible to re-broadcast the appropriate parts of a captured four way handshake and connect to the router? If not why so?
|
My VPS has been shut down now again for the second time for TOS violations (email spam), and I really need some help. I have been battling with my server being attacked for over a year now. Most of my sites are running Joomla ranging from 1.5 installs (which cannot be upgraded because the customers have declined the up... |
I have given three certs to be install on nginx
AddTrustExternalCARoot.crt
PositiveSSLCA2.crt
www_example_com.crt
So I concat them into a chained cert
cat www_example_com.crt PositiveSSLCA2.crt AddTrustExternalCARoot.crt > example.com.cert
My questions:
Is appending the AddTrustExternalCARoot.crt really needed for ... |
I was reading here on Hashes and Salts and I thought about another method to do user authentication. I need your thoughts on this as I might be overlooking something.
Scenario:
For web application authentication, the general trend is to hash the password appending a random salt, with a strong hash function. The random ... |
Recently i came across one donation site which gets credit card info and makes donations, like the above donation site most of the site broughts donation on their own donation page instead of redirecting to external payment gateway pages
My questions are as follows
As they are getting info at their domain based page ... |
According to this bug report, the first vulnerability can leak sensitive information.
But since it doesn't mention what information to leak, I guess it would be the stack? And how could this help in exploit development?
|
In recent news, CNET has reported requests for passwords, hashing and/or encryption algorithms and salts from U.S. government agencies:
The U.S. government has demanded that major Internet companies divulge users' stored passwords, according to two industry sources familiar with these orders, which represent an escala... |
I was just reading this answer to the question Why is the same origin policy so important?
Basically, when you try to make an XMLHttpRequest to a different
domain, the browser will do one of two things:
If it's a GET or POST request which meets certain limits (which the makers of the standard have determined to add n... |
Presumably the SHA is for deriving the AES key from the shared secret. Where else is the hash used?
ECDH just does ECC (no hashing). RSA does masking and padding but this doesn't involve the negotiated hash, does it?
For AES-GCM we don't need to stir the IV or anything between messages, we can just increment, so as far... |
I have the need to isolate a virtual machine created with Virtualbox from the local network but I need to provide internet access to that machine.
It is the first time that I face this kind of problem, different solutions came up in my mind:
create a VLAN
use a DMZ
use a firewall in the host machine filtering communic... |
I want to block some specific URLs and DNS addresses.
I am thinking if I buy a manageable switch (More specific would be TLSF1024D)
What can I do to block some sites, and specific URLs like http://www.youtube.com/watch?v=fGH7NxSEGtA , that are not suitable for children.
|
OpenSSH 6.2 offers the following key exchange algorithms by default
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
diffie-hellman-group-exchange-sha256
diffie-hellman-group-exchange-sha1
diffie-hellman-group14-sha1
diffie-hellman-group1-sha1
The group size of the first three is obvious. The same holds for th... |
Firstly, let me start by saying that I am not attempting to hack anyone or anything (not that I would know how or where to begin, if I were).
For illustration purposes, let's call the primary key owner A, the "good" public key holder GOOD, and the "evil", MITM public key holder BAD.
Also, assume this MITM is in your IS... |
An unexpected duplicate HTTP GET operation triggered an "unusual event" report on my web site. The duplicate came from the web site of "Trendmicro.com" who seem to be in the internet security business. It's just my guess, but I suspect they collect sample queries on behalf of their clients, then submit those queries... |
I called my domain registrar (unnamed here but not difficult to find out and a major provider) about a year ago to have them change some DNS settings. While on the phone, the customer service rep had me speak my password (letter by letter) to prove my identity. It just dawned on me: is my domain registrar therefore sto... |
I had a conversation today and someone challenged me as to why you would need to verify the identity of a user calling a service desk with anything other than their company email. Granted, I know these can be spoofed, but the upper-level executive didn't.
I have been pressing to have at a minimum a user-specific PIN... |
In the past I've heard about a scheme to prove your identity online in places like forums, without having to create an account.
When posting, the user would enter a password which is then heavily hashed and displayed publicly along with the post. This way the user can prove his identity between posts without having to ... |
I've read elsewhere (http://forums.udacity.com/questions/6028436/bcrypt-not-suitable-for-pythongae) that bcrypt is not suitable for use on Google App Engine. What are some good ways to create a user signup/login system (with usernames/emails & passwords) without rolling your own when using Google App Engine for Python?... |
I cannot differentiate between Instrumentation and Virtual machine introspection. Since the goal of Virtual Machine introspection is to examine the properties of a target through virtual machine monitor then what is the purpose and use of instrumentation technique.
|
I want to make my game extremely hard to decompile. So I've come up with the idea of a program which will contain my game's code, coded in a custom language, and which will translate that code into Java code during runtime. (So it's kind of like a virtual machine is running on top of Java's virtual machine, or at least... |
A casual message exchange on reddit yesterday got me thinking whether it might be possible to design a protocol that removes the need for users to remember a unique password for every service (s)he connects to.
The idea is that essentially each user supplies identifying credentials (name, date of birth, city of birth) ... |
What would be the best ways to protect sensitive data stored on a server/drive that gets stolen? The confidentiality of the data is what is important, not retrieving it. Obviously, physical means are one way, but lets assume the thieves devised an elaborate heist to bypass the physical security. This data would ruin th... |
Im a current student going for my Bachelors in Network Administration and would like to get in to the security side of things. I have my Network+, Security+ as well as the A+ and a MCTS.
I currently do IT support for two companies mostly supporting Exchange and iOS. What kind of skills are most sought after and require... |
I came through a post on Offensive Security and while reading , the author stated that:
At next SEH (when using a SE Handler address that starts with a null byte), we usually will put some code to jump back. After all, the null byte would acts as a string terminator and it does not make sense to put something after ... |
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