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.
2
votes
1answer
175 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 ...
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votes
3answers
538 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 ...
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 ...
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?
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votes
2answers
116 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
154 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 ...
4
votes
1answer
202 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 ...
6
votes
1answer
135 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?
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3answers
891 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 ...
