beware Windows Vista SP1
Bruce Schneier is worried about the Microsoft Vista Service Pack 1 implementation of the flawed Dual_EC_DRBG random number generator.
He explained the flaw last month, noting that Dual_EC_DRBG "includes an algorithm that is slow, badly designed and just might contain a backdoor for the National Security Agency" Schneier continued:
"The math is complicated, but the general point is that the random numbers it produces have a small bias. The problem isn't large enough to make the algorithm unusable [...] but it's cause for concern."
(For math geeks, the obligatory Wikipedia article on elliptic curve cryptography is here.)