CVE-2009-5138

GnuTLS anterior a 2.7.6, cuando el indicador GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT no está habilitado, trata certificados X.509 de versión 1 como CAs intermedios, lo que permite a atacantes remotos evadir restricciones mediante el aprovechamiento de un certificado X.509 V1 de un CA confiable para emitir certificados nuevos, una vulnerabilidad diferente a CVE-2014-1959.

The GnuTLS library provides support for cryptographic algorithms and for protocols such as Transport Layer Security. It was discovered that GnuTLS did not correctly handle certain errors that could occur during the verification of an X.509 certificate, causing it to incorrectly report a successful verification. An attacker could use this flaw to create a specially crafted certificate that could be accepted by GnuTLS as valid for a site chosen by the attacker. A flaw was found in the way GnuTLS handled version 1 X.509 certificates. An attacker able to obtain a version 1 certificate from a trusted certificate authority could use this flaw to issue certificates for other sites that would be accepted by GnuTLS as valid.