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seen Nov 24 at 17:24

Jul
18
comment Modes of operation that allow padding oracle attacks
Can you define what you mean by padding oracle attacks? If you count switching the order of the blocks around in ECB mode to be a padding oracle attack, then you're using a non-standard meaning of the phrase (since in that case you're not even attacking the padding function nor using it as an oracle). Do you maybe simply mean chosen-ciphertext attacks on confidentiality?
Jul
16
comment Does having a known plaintext prefix weaken AES256?
What research have you done? This is already answered by several questions on this site, e.g., crypto.stackexchange.com/q/1512/351, crypto.stackexchange.com/q/3952/351. (If you'd searched, you should have found them immediately; and they already show up in the related questions list.) We expect you to do a significant amount of research before asking here, including searching on this site for other questions and answers that might shed light on your question. At worst, it will help you frame a better, more focused question; at best, it might answer your question for you.
Jul
14
awarded  Nice Answer
Jul
14
awarded  Nice Answer
Jul
10
comment CBC-MAC length extension attack with IV simulation
Please edit the question to make clearer what the problem is. We don't have the second part of 49th problem in Matasano's problem set memorized in our head. Right now, the question does not seem answerable to me. Also, I suggest you edit the question to tell us what research you've done, what attacks on CBC-MAC you are familiar with, and what you've tried.
Jul
10
comment Choosing primes in the Paillier cryptosystem
I can't understand what you are asking. What does "Give me a reference if proof for above equation complex otherwise provide a proof." mean? Also, what research have you done? Did you read the original research paper?
Jul
7
revised Password-based encrypted key storage?
fix typo caught by e-sushi
Jul
7
revised Password-based encrypted key storage?
added 34 characters in body
Jul
3
answered Password-based encrypted key storage?
Jul
2
comment Password-based encrypted key storage?
@otus, RFC 5959 only uses AES in ECB mode if the plaintext is exactly 128 bits long. That is not malleable (not in any useful way that would enable related-key attacks).
Jul
2
awarded  Curious
Jun
30
awarded  Revival
Jun
30
revised Associative standard cryptographic hash function
added 1251 characters in body
Jun
30
answered Associative standard cryptographic hash function
Jun
26
awarded  Custodian
Jun
26
reviewed Leave Closed RSA: Common modulus attack problem
Jun
26
comment RSA: Common modulus attack problem
CGFox, rather than editing your question here, it would be better to propose an edit to the answer on the other thread that adds a clarification of how to deal with a negative exponent, i.e., what it means to raise to the $s_1$ power if $s_1$ is negative.
Jun
26
reviewed Leave Open Is HMAC needed for a SHA-3 based MAC?
Jun
26
reviewed Looks OK Testing hardware random number generators?
Jun
25
comment Choose a random number that is different from a bunch of other secret numbers
@CedricMartin, the standard commutative encryption algorithms (e.g., Pohlig-Hellman) do not require a TTP to hold any keys. The prime $p$ is public and shared by everyone; each participant's exponent is secret and is their key and is generated by them and known only to them. No TTP is needed. If you have questions how to use commutative encryption in practice, I suggest reading the existing questions, then posting a new question if it's not covered by the ones that are already on this site.