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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.


May
18
comment How does an attacker know when he has the password?
@mucaho Added additional pseudocode as requested.
May
18
comment How does an attacker know when he has the password?
@NeilSmithline Yes, that is true, but for simplicity's sake and to answer the specific question of how the attacker would know the right password for the hash, I didn't go into that.
May
18
comment ASP.NET Machinekey encryption
@Jake Yes. The IV is embedded within the output data.
May
18
comment Disadvantages of disabling RC4 in SSL/TLS
@R15 Good point, though just mentioning RC4 alone may not be sufficient due to future developments. I've just put a generic note in there.
May
18
comment Disadvantages of disabling RC4 in SSL/TLS
@StackzOfZtuff Yes. ECDSA is the Elliptic Curve variant of DSA. Keep in mind that this is not the same as ephemeral. Unfortunately different implementations make it confusing, but the generally accepted format is to use the -E suffix (e.g. DHE) to signify ephemerality, and the EC- prefix (e.g. ECDH) to specify that it's an Elliptic Curve variant. If it's both elliptic curve and ephemeral, you'd use both: ECDHE.
May
18
comment Disadvantages of disabling RC4 in SSL/TLS
@StackzOfZtuff Sure. DSA long-term keys can be stored in certificates and used for the key exchange, just like RSA.
May
18
comment What is encryption by RSA with AES?
@AlpA No. We have The DMZ for general chat, but there are no private messages. It would defeat the point of having public discussion which can be referred to later by others.
May
18
comment Firebug reports SHA-1 certificate error
Ah - I worked it out. The certificate has a list of Subject Alternative Name records, including *.googleapis.com. For some reason Google chose to set the storage domain as the CN.
May
18
comment Firebug reports SHA-1 certificate error
All that said, I haven't quite worked out why a certificate with a common name of *.storage.googleapis.com is considered correct for the domain ajax.googleapis.com...
May
18
comment Disadvantages of disabling RC4 in SSL/TLS
Side note: when I say XP can "only" use RC4, that's a simplification, as it also supports DES, which is arguably better in some respects if you use it as part of 3DES. However, I don't recommend 3DES in TLS 1.0 (the only protocol it would make sense to add it to for compatibility) due to BEAST and the meet-in-the-middle attack against 3DES.
May
18
comment Disadvantages of disabling RC4 in SSL/TLS
I'm not sure that your advice holds in all situations - many very important web applications and web services are only used by legacy systems which do not support AES, but only DES and RC4. In such cases, disabling RC4 would prevent access from these devices. It's not all about how important the data is - there are also environmental factors.
May
18
comment What is encryption by RSA with AES?
@AlpA If you'd split it individually you'd have found that most of the questions you wanted to ask were already answered elsewhere, so you only needed to ask one or two specific ones to cover the more specific parts of your question.
May
18
comment What is encryption by RSA with AES?
Sorry, yes. 2^56 64-bit blocks. I'll fix it.
May
18
comment What is encryption by RSA with AES?
Also, for future reference, we usually request that you ask one question per post. You've stuck a lot of stuff into one place here, which is probably why someone downvoted. Take a look at our tour page and the help center for more information on how StackExchange works.
May
18
comment What is encryption by RSA with AES?
I think you have a typo - it's CBC, not CBS.
May
18
comment How do I prevent SSD file recovery?
@Sina As long as TRIM runs on the sector, you're fine. A potential failure case is if you get a power outage immediately after deleting something, before TRIM gets round to clear the affected sectors. Some drive firmwares have also been known to implement a faulty TRIM algorithm, but these are mostly documented and fixed. Check for firmware updates from your manufacturer.
May
17
comment Windows Passwords
The first step would not to be to bruteforce the SAM hashes - it'd be to pull the LSA stored secrets to find the plaintext cached passwords.
May
16
comment Is there a full disk encyption software that shows different content depending on what password has beeen used?
@Damon Also, you can just turn off the TPM and use BitLocker in passphrase mode, which means you (a) don't have to rely on the TPM, and (b) can use a passphrase of any number of 7-bit ASCII characters (I don't think there's a limit). My passphrase easily breaches 200 bits according to KeePass' estimation, and we have some automatic-entry ones at work that I guarantee are in excess of 500 bits.
May
16
comment Is there a full disk encyption software that shows different content depending on what password has beeen used?
@Damon The basic PIN in TPM mode is a numeric identifier, and you're right that its entropy is relatively low - 68 bits or so at best. In enhanced PIN mode with a TPM, you can use 20 7-bit ASCII characters, which is more like 132 bits of entropy. Keep in mind that the TPM actively rate-limits you so brute force against it should not be possible.
May
15
comment Is there a full disk encyption software that shows different content depending on what password has beeen used?
@Damon I would also point out that BitLocker has been reviewed by plenty of people in the security community. Just because there's no code available doesn't mean people aren't disassembling and looking at things. The full NT6.1 code is also available under shared license, which a fair number of organisations have access to.