RSA private keys biased toward 0 bits can be factored by swapping a hard math problem for an easy one: integer factorization becomes polynomial factorization.
We found hundreds of real-world keys vulnerable to this. Many traced to a type mismatch in CompleteFTP (now patched): each 32-bit limb got only 8 bits of randomness. We recovered 603 RSA and 74 DSA private keys. https://t.co/C2jcxVW9WG