CVE-2018-0495

Libgcrypt en versiones anteriores a la 1.7.10 y versiones 1.8.x anteriores a la 1.8.3 permite un ataque de canal lateral por caché de memoria en las firmas ECDSA que se puede mitigar mediante el uso de la ocultación durante el proceso de firmado en la función _gcry_ecc_ecdsa_sign en cipher/ecc-ecdsa.c. Esto también se conoce como Return Of the Hidden Number Problem o ROHNP. Para descubrir una clave ECDSA, el atacante necesita acceso a la máquina local o a una máquina virtual diferente en el mismo host físico.

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. 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. 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. Various other issues were also addressed.