DSA Bias Vulnerability↑
Consequences↑
Compromise of private signing key
Access required for attack↑
The attacker needs only to obtain a small number of signatures
Explanation↑
This vulnerability affects DSA signature operations. Before April 2016, the standard Oracle Java crypto provider contained a flaw that allowed the private key to be calculated based only on the values of 3-5 signatures.
The attack method is well-known and has appeared in academic publications (see below).