57,545 reputation
17140236
bio website en.wikipedia.org/wiki/…
location United Kingdom
age 27
visits member for 3 years, 9 months
seen Jul 15 at 23:36

Pentester, ex-developer, security researcher, reverse engineer, electronics tinkerer, internet activist, zombie eradicator, promulgator of useless facts, shrubbery inspector, bacon aficionado, devourer of donuts.

Strengths: Security, Crypto, Win32 API, C#, .NET, PHP, x86 assembly

All answers and comments are encrypted with ROT256-ECB.

Opinions are my own. Advice provided with no warranty.


Jun
10
comment Is it secure not to have csrf protection in login forms?
@AviD Session fixation issues can be exploited to produce a session donation in some cases, but usually they're separate. You're correct about forcing them to log in with your creds though.
Jun
10
comment Is it secure not to have csrf protection in login forms?
@AviD Not quite the same. Session fixation is where you set a session cookie in their browser before they log, but the application doesn't change the session ID on login, so you then know the session ID and can hijack their session. This gives you full access to their account. Session donation attacks involve using CSRF to log them into your account, not theirs, without them realising.
Jun
9
comment Potential collision with hash password
@Kruncho I'm not sure what you're asking there. If you're referring to why they're used in Linux or Windows by default, I don't know the answer. It's probably something to do with a lack of NIST approval, or just that it's always been done in a particular way. Microsoft provides PBKDF2 in the .NET Framework though (via the Rfc2898DeriveBytes class) and bcrypt is available as a command-line tool on Linux. I'm also pretty sure that some Linuxes do support bcrypt hashes for logon (in /etc/shadow), either natively or with additional PAM modules.
Jun
5
comment Can DUKPT BDK be 192 bits?
Keep in mind that 3DES is vulnerable to a meet-in-the-middle attack, which reduces the time complexity of 112-bit 3DES-EDE key option 2 to 2^57 operations with a storage requirement of 2^56 64-bit blocks (512 petabytes). This is considered feasible, since a large number of organisations have SANs and other storage clusters of or exceeding this size. The same attack also applies to 3DES-EDE with a 168-bit key (i.e. three independent 56-bit keys) with a time complexity of 2^112 and the same 512PB storage cost.
May
28
comment What is the “Moose” worm and how can I protect myself from it?
Keep in mind that the "ShieldsUP service from GRC.com" is a product created by Steve Gibson, who has demonstrated a fantastic lack of understanding of network technologies. He's a salesman and pundit, not a security expert. There are numerous reports that ShieldsUP doesn't actually properly scan ports, and may return both false positives and false negatives.
May
27
comment Is this way of encoding cryptographic hashes safe?
@apsillers Ah, I see what you're saying - there's a potential for collision between a pair of 3-char and 2-char base62 units where the encoding could be 3-then-2 or 2-then-3.
May
27
comment Is this way of encoding cryptographic hashes safe?
That would only be true if ONLY two base62 characters were put into the string regardless of what the three base16 characters encode to. I don't think that's the case though - I think all 3 characters are added and the string gets longer.
May
27
comment Is this way of encoding cryptographic hashes safe?
@apsillers My understanding is that they're not truncating each block, but rather concatenating all of that data together, such that there's no loss of information even if you can't trivially identify which ones were 3-char and which ones were 2-char.
May
27
comment Is it safe to publish some internal IP of my company?
@justarandomguy Right, but you've posted this on Meta Sec.SE, not Sec.SE.
May
27
comment Can attackers get anything with DoS attacks except crashing the service?
@RoryAlsop Yikes. Sounds ideal!
May
27
comment Why Adobe is recommending McAfee security scan during flash player installation?
@MilchePatern You're talking about the general security of Flash, which is a totally different matter to this specific affiliate marketing campaign. Also, Steve Jobs was a businessman and marketing director, not an engineer or coder - his thoughts on the security of Flash are irrelevant to this particular topic. Even if we were to entertain his opinions, they mostly rely upon the complaint that Flash is proprietary, which again has little bearing on the actual security of the product.
May
27
comment Can I use AES CTR mode to encrypt files with same key and nonce?
@Rak The stuff in my answer.
May
22
comment Can I use AES CTR mode to encrypt files with same key and nonce?
I'm not sure how you're inferring that from the question.
May
22
comment Can I use AES CTR mode to encrypt files with same key and nonce?
If his attack model is that an attacker can't get access to the encrypted data, why encrypt the data in the first place?
May
22
comment What is Logjam and how do I prevent it?
@Atsby You could say the same about drone attacks.
May
20
comment Offline RSA strong prime test similar to Phuctor?
You should note that the factored 4096-bit key was a corrupt subkey, not a real generated key. As such it had no real-world impact.
May
20
comment Should diffie-hellman parameters be unique to a vhost
Yes, it matters, though 2048-bit makes the point rather moot.
May
20
comment What is Logjam and how do I prevent it?
@ThomasPornin I figured there was some crypto wizardry behind the precomputation that I wasn't aware of. Your answer is excellent, by the way. I understand it better than I did before.
May
20
comment PayPal encrypted with obsolete cryptography
@cburatto The selected cipher suite is agreed upon by both the client and server, depending upon support and suite priorities.
May
19
comment How to escape a cookie to cause split response?
You can only exploit it as a splitting attack if you can cause encoded values to be decoded into the cookie value, e.g. passing %0D%0A into the URL producing a raw CR+LF in the cookie.