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seen Mar 28 at 23:03

Mar
28
asked Keystore and configuration file
Jan
20
asked Is there a kind of OS entropy pool on Windows systems?
Jan
3
asked RSA - Why should we sign hash rather than raw content?
Jan
2
asked Smart Card - Entropy during on-board public key generation
Dec
31
comment Issue about randomness : what if random looks “human” ?
@DW Please accept that there may be "non english" user on this website, so my english may not be as perfect as you wish. An exemple of what I was wondering, we often read for One Time Pad : should be random AND never reuse. It can not be truely random if you remove "already use pad" from possible pad.
Dec
6
comment SHA1 Collisions - what about practical attacks?
Great answer, really !!
Dec
5
comment SHA1 Collisions - what about practical attacks?
Thanks, such a great answer ! But "thus allowing forgery of a slightly different certificate beneficial to the attacker" , when it is about hash fonction, "slightly" difference in input doesn't mean "near output", so why is it an advantage to have chosen fields and "slightly" different ?
Dec
5
accepted SHA1 Collisions - what about practical attacks?
Dec
5
comment SHA1 - SSL/TLS Cipher Suite
@acid Thanks for your comment, but actually, padding could be used to resolve the "modulus size" problem, no ? As when you want to encipher large file with public key.
Dec
5
awarded  Commentator
Dec
4
revised SHA1 Collisions - what about practical attacks?
added 8 characters in body
Dec
4
asked SHA1 Collisions - what about practical attacks?
Dec
4
comment SHA1 - SSL/TLS Cipher Suite
@CodesInChaos Thanks for answering. I am know wondering why CA signs the certificate hash rather than the "raw content", there couldn't be collisions, I guess it is obvious, like performances when signing, perhaps also signature size, but x509 certificate are rather short file. Any idea ?
Dec
4
comment SHA1 - SSL/TLS Cipher Suite
@CodesInChaos In fact, an attacker wouldn't need to get the CA to sign the "fake" certificate, because if the two certificates have the same hash, they have the same signature (private key + hash). So the attacker can just get the signature of the "original" certificate (public info) and appends this signature on the fake one. No ?
Dec
1
revised SHA1 - SSL/TLS Cipher Suite
I think you mean "still secure" and note "not secure"
Dec
1
accepted SHA1 - SSL/TLS Cipher Suite
Dec
1
comment SHA1 - SSL/TLS Cipher Suite
@CodesInChaos Ok I see, the "attack" is before CSR is made.
Dec
1
revised SHA1 - SSL/TLS Cipher Suite
added 297 characters in body
Dec
1
comment SHA1 - SSL/TLS Cipher Suite
Ok but i can't understand how attackers could forge SHA1 certificate signature, as the hash is still "protected" by the signature (CA private key). So forgin the hash with collisions, ok, but one would detect that hash is not trusted anymore (signature would'nt be the same). I miss something ?
Dec
1
suggested approved edit on SHA1 - SSL/TLS Cipher Suite