Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
nakedsecurity.sophos.com
Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
1–10 of 128 posts
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#2We talk about how JavaScript delivered from a webserver can never be a secure crypto platform, but of course in reality the problems are far more mundane.
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#3Very interesting article, thank you.
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#4We talk about how JavaScript delivered from a webserver can never be a secure crypto platform, but of course in reality the problems are far more mundane.
s/mundane/interesting/
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#5Really drives home what many people were saying about the authors not merely being bad at cryptography but programming in general...
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#6As the lead developer for Cryptocat, I must say this is really a great example of how to write a post-mortem for a security bug. Sophos bloggers are always worth reading.
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#7I'm a complete noob when it comes to cryptography. I understand that having a PRNG that doesn't return numbers with even distribution across a range is bad. Extreme example would be something like http://xkcd.com/221/.
But could someone explain how an attacker can take advantage of the fact that 0 is returned ~1% more often than other digits? It this flaw alone sufficient to break cryptocat? Or does it simply make brute forcing easier when combined with other crypto flaws?
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#8Interesting though this is, all it really shows is that there is a bias in the random number generation.
I would be more interested to know if this is sufficient to break Cryptocat. Would this really make a brute force attempt much easier?
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#9Really drives home what many people were saying about the authors not merely being bad at cryptography but programming in general...
I upvoted this because, of course, it confirms my own biases, but kind of wish I hadn't, because we're not helping with comments like these.
Re: Anatomy of a pseudorandom number generator – visualising Cryptocat's buggy PRNG
#10[deleted]