USN-3692-2: OpenSSL vulnerabilities

USN-3692-1 fixed a vulnerability in OpenSSL. This update provides the corresponding update for Ubuntu 12.04 ESM. Original advisory details: Keegan Ryan discovered that OpenSSL incorrectly handled ECDSA key generation. An attacker could possibly use this issue to perform a cache-timing attack and recover private ECDSA keys. (CVE-2018-0495) Guido Vranken discovered that OpenSSL incorrectly handled very large prime values during a key agreement. A remote attacker could possibly use this issue to consume resources, leading to a denial of service. (CVE-2018-0732) Alejandro Cabrera Aldaya, Billy Brumley, Cesar Pereida Garcia and Luis Manuel Alvarez Tapia discovered that OpenSSL incorrectly handled RSA key generation. An attacker could possibly use this issue to perform a cache-timing attack and recover private RSA keys. (CVE-2018-0737)