CVE-2016-7444

La función gnutls_ocsp_resp_check_crt en lib/x509/ocsp.c en GnuTLS en versiones anteriores a 3.4.15 y 3.5.x en versiones anteriores a 3.5.4 no verifica la longitud de serie de una respuesta OCSP, lo que podría permitir a atacantes remotos eludir un mecanismo de validación destinada a certificados a través de vectores que involucran bytes finales dejados por gnutls_malloc.

A flaw was found in the way GnuTLS validated certificates using OCSP responses. This could falsely report a certificate as valid under certain circumstances.

USN-3183-1 fixedCVE-2016-8610 in GnuTLS in Ubuntu 16.04 LTS and Ubuntu 16.10. This update provides the corresponding update for Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. Stefan Buehler discovered that GnuTLS incorrectly verified the serial length of OCSP responses. A remote attacker could possibly use this issue to bypass certain certificate validation measures. This issue only applied to Ubuntu 16.04 LTS. Shi Lei discovered that GnuTLS incorrectly handled certain warning alerts. A remote attacker could possibly use this issue to cause GnuTLS to hang, resulting in a denial of service. This issue has only been addressed in Ubuntu 16.04 LTS and Ubuntu 16.10. It was discovered that GnuTLS incorrectly decoded X.509 certificates with a Proxy Certificate Information extension. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 16.10. It was discovered that GnuTLS incorrectly handled certain OpenPGP certificates. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. Various other issues were also addressed.