CVE-2018-16151

In verify_emsa_pkcs1_signature() in gmp_rsa_public_key.c in the gmp plugin in strongSwan 4.x and 5.x before 5.7.0, the RSA implementation based on GMP does not reject excess data after the encoded algorithm OID during PKCS#1 v1.5 signature verification. Similar to the flaw in the same version of strongSwan regarding digestAlgorithm.parameters, a remote attacker can forge signatures when small public exponents are being used, which could lead to impersonation when only an RSA signature is used for IKEv2 authentication.

In verify_emsa_pkcs1_signature() in gmp_rsa_public_key.c in the gmp plugin in strongSwan 4.x and 5.x before 5.7.0, the RSA implementation based on GMP does not reject excess data after the encoded algorithm OID during PKCS#1 v1.5 signature verification. Similar to the flaw in the same version of strongSwan regarding digestAlgorithm.parameters, a remote attacker can forge signatures when small public exponents are being used, which could lead to impersonation when only an RSA signature is used for IKEv2 authentication.

En verify_emsa_pkcs1_signature() en gmp_rsa_public_key.c en el plugin gmp en strongSwan en versiones 4.x y 5.x anteriores a la 5.7.0, la implementación RSA basada en GMP no rechaza los datos sobrantes tras el algoritmo OID cifrado durante la verificación de firmas PKCS#1 v1.5. De forma similar al error en la misma versión de strongSwan relacionado con digestAlgorithm.parameters, un atacante remoto puede falsificar firmas cuando se emplean pequeños exponentes públicos, lo que podría conducir a una suplantación cuando solo se emplea una firma RSA para la autenticación IKEv2.