6,688 reputation
11734
bio website github.com/CodesInChaos
location Frankfurt, Germany
age
visits member for 3 years, 4 months
seen 12 hours ago

12h
revised Cracking Password
deleted 6 characters in body
13h
reviewed Approve suggested edit on Level 4 merchants becoming PCI Compliant
Nov
25
comment Are there any disadvantages to encrypting the password hash?
IMO encrypting the hash is superior to a pepper/secret salt. Security wise they're the same, but a key can be changed (simply decrypt and re-encrypt the data) and it integrates better with a HSM.
Nov
25
comment Does too long a salt reduce the security of a stored password hash?
@Iszi The point of a salt it to prevent multi-target attacks, so I don't deny the security benefit of unique salts. But precomputation is just one variant of a multi-target attack. IMO people worry too much about rainbow tables compared with live multi-target attacks.
Nov
25
comment Does too long a salt reduce the security of a stored password hash?
No competent attacker would bother to create a rainbow table for 3), a direct multi-target attack is at least as efficient. A rainbow table is only useful if you want to crack passwords with the same hash at different times.
Nov
25
comment Company decrypting SSL, is it common?
Not in civilized countries.
Nov
22
comment PHP secure random number generator
@JoelL Unlike opening /dev/urandom by yourself, MCRYPT_DEV_URANDOM works on windows as well.
Nov
22
comment Please help me to find the Hash algorithm and decrypt the password
40 hex character = 20 bytes = 160 bits. My first guess would be SHA-1.
Nov
22
comment How effective are password checking websites?
Isn't your 48 days too small by a factor of 1000 or so?
Nov
14
comment Is TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 a safe cipher suite to use?
AFAIK TLS 1.2 is still MAC-then-encrypt, so I'd hesitate to use CBC.
Nov
14
comment Java SecureRandom doesn't block? How?
But you can only retrieve entropy securely from random.org if you have enough entropy to create a secure SSL connection. So you have a chicken-egg problem.
Nov
13
comment Does encrypting the message protect it against length extension attacks
This should prevent the length extension, but as Xander noted using MAC-then-encryption causes other difficulties, so it's still a bad idea. If the encryption is a stream cipher (including AES-CTR) it's probably secure, if it's CBC you're almost certainly fucked.
Nov
13
answered AES 128bit decryption using a key longer than 16 bytes
Nov
11
comment How bad is it to truncate a hash?
"the blackbox should not be able to know the original 8 bytes." and "Some blackbox take a 8 byte value" sounds like a direct contradiction to me.
Nov
6
comment Hashing a hard drive before shutdown
ZFS and TahoeLAFS have some similar features.
Nov
4
comment Are there any instant messaging systems that offer resistance to traffic analysis?
Not an instant messages, but AGL's Pond is a messaging system that takes traffic analysis seriously.
Nov
4
comment How can Tor be considered a standard tool for achieving anonimity, given that it is created by the government?
You can verify that the distributed code for Tor relays does not log. But you cannot verify that actual relays do not log. Some certainly do. But for this issue it doesn't matter who created Tor, but who runs relays.
Nov
4
revised TextSecure/WhisperPush instant messaging by Open Whisper Systems: End-to-end encrypted or not?
added 243 characters in body
Nov
4
answered TextSecure/WhisperPush instant messaging by Open Whisper Systems: End-to-end encrypted or not?
Nov
4
comment TextSecure/WhisperPush instant messaging by Open Whisper Systems: End-to-end encrypted or not?
Whisper has nothing to do with Open Whisper Systems / TextSecure. It's just a similar name.