6
votes
How to prevent power analysis on software level?
Software can do a number of things to thwart power analysis. Fundamentally, power analysis looks at power consumption to extract information about operations carried out inside the device. To make ...
- 1,236
4
votes
If ChaCha20 only has 128 bits, is it secure?
Assume that ChaCha20 only has 128-bit, is it secure?
Let us think this through; suppose that our best attack is trying each key individually (which, as far as we know, is true), and that our ...
- 140k
4
votes
When using AES-256 in combination with HMAC-SHA, should we use SHA-256 or SHA-512?
That pairing is considering security against the most vulnerable aspect - collision resistance of hash functions.
However, when used in SSL/TLS, hash function is most likely used for key derivation or ...
- 8,283
3
votes
Accepted
Secure encryption in the presence of a keyservice
No. CBC decryption has a neat feature that allows recovery from errors.
Not having the IV is essentially an error and only corrupts the first block. So if an attacker decrypts using an all zero IV, ...
- 1,236
3
votes
Accepted
Why is IV in RFC8448 examples only 12 octets instead of 16?
the IV in examples is only 12 bytes long instead of 16, which is required for AES-128-GCM.
That is incorrect; while GCM supports any nonce length, it is both simpler and more secure with 12 byte ...
- 140k
2
votes
Accepted
How does JOSE/JWE make use of ECDH when encrypting/decrypting messages?
You are talking about IES or ECIES in the context of Elliptic Curves. The way it works is that there is a static key pair of the receiver, for which the public key first needs to be trusted by the ...
- 90.2k
2
votes
How to determine cryptographic properties of AES S-Box?
There are a number of different aspects to this, for example one can determine the nonliearity of the AES Sbox as a vectorial boolean function see here
The correlation immunity of the AES Sbox can ...
- 20k
1
vote
Accepted
AES CBC with random IV but key from PBKDF2 with same salt
The point of salting is to prevent an attacker preparing a rainbow table - that is, for every interesting password, calculate the hash, and then look to see if any of the password hashes match.
For an ...
1
vote
Where in the TLS 1.3 record is the sequence number located?
The sequence numbers are never explicitly transmitted, but are calculated independently by both sides starting from 0 with separate counts for send and receive.
- 20k
1
vote
How to prevent power analysis on software level?
If one makes the software "look" like it could be in hardware, you can make something is fixed time and relative fixed power. This involves making decisions on how the hardware will behave ...
- 4,524
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