Mozilla Network Security Services (NSS) before 3.15.4, as used in Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, SeaMonkey before 2.24, and other products, does not properly restrict public values in Diffie-Hellman key exchanges, which makes it easier for remote attackers to bypass cryptographic protection mechanisms in ticket handling by leveraging use of a certain value.