attacks using information leaked by implementations of cryptographic algorithms to obtain information about keys or (plaintext) data, instead of (or additional to) using cryptographic weaknesses.
10
votes
3answers
899 views
Known methods for constant time (table-free) AES implementation using 'standard' operations?
There are several known methods for implementing AES in constant time using SIMD operations, mostly based around fast byte shuffling (for instance Hamburg and Kasper/Schwabe). Are there any similar ...
10
votes
3answers
545 views
How practical are side-channel attacks and how much of a concern are they?
I see a lot of research in very sophisticated side-channel attacks on crypto systems. Most (but definitely not all) seem to follow a trend, namely, the crypto system does something very dumb like ...
6
votes
1answer
136 views
Are more complex algorithms easier to break with timing attacks?
Is there a point where increasing the complexity of an encryption algorithm will make it easier to break using a timing attack?
Or is there no connection here at all?
4
votes
1answer
204 views
AES timing attacks
I'm just interested in cryptography, so please don't expect me to be an expert. ;) I recently read about AES cache timing attacks and found it very interesting. I read the article Cache-timing attacks ...
2
votes
2answers
155 views
Stopping timing attacks on AES: Why is it important to prevent the OS from interrupting the AES computation?
I read the paper Cache-timing attacks on AES (by Daniel J. Bernstein), but I don't seem to understand everything. The author dedicates a long section on how to prevent the OS to interrupt an AES ...
2
votes
1answer
179 views
Extract private RSA key from USB cryptographic token using Bardou et al. attack (varian of “million message attack”)
There is a side channel attack on tamper-resistant USB cryptographic tokens using padding-oracle, described by Bardou, Focardi, Kawamoto, Simionato, Steel and Tsay, titled "Efficient padding oracle ...
2
votes
1answer
126 views
What is “Blinding” used for in cryptography?
What does "blinding" mean in cryptography, and where do we usually use it? Can you describe a sample implementation?
2
votes
2answers
117 views
Information leakage in real-time voice encryption
I saw some time ago a post discussing the issues surrounding encryption of speech/voice in VoIP and how it can leak information (can't find it now). Can someone provide an insight into some of the ...
2
votes
2answers
112 views
Timing attack on modular exponentiation
It is known that computing $a^x \bmod N$ takes $O(|x| + \mathrm{pop}(x))$ multiplications modulo $N$, where $|x|$ is the number of bits of $x$ and $\mathrm{pop}(x)$ is the number of $1$ bits (Hamming ...
