Vigil@nce - GnuTLS: incoherence of signature algorithms
March 2015 by Vigil@nce
This bulletin was written by Vigil@nce : http://vigilance.fr/offer
SYNTHESIS OF THE VULNERABILITY
An attacker can use an incoherent X.509 certificate with an
application linked with GnuTLS, in order to weaken the security
level.
Impacted products: Debian, Ubuntu, Unix (platform)
Severity: 1/4
Creation date: 24/03/2015
DESCRIPTION OF THE VULNERABILITY
An X.509 certificate indicates several signature algorithms.
However, GnuTLS does not check if the "signatureAlgorithm.algorithm"
and "tbsCertificate.signature.algorithm" are the same.
An attacker can therefore use an incoherent X.509 certificate with
an application linked with GnuTLS, in order to weaken the security
level.
ACCESS TO THE COMPLETE VIGIL@NCE BULLETIN
http://vigilance.fr/vulnerability/GnuTLS-incoherence-of-signature-algorithms-16448