Actu
Vigil@nce: GnuTLS, X.509 troncated with null
August 2009 by Vigil@nce
An attacker can invite the victim to connect to a SSL site using a
X.509 certificate with a field containing a null character, in
order to deceive the victim.
Severity: 2/4
Consequences: data reading
Provenance: internet server
Means of attack: no proof of concept, no attack
Ability of attacker: expert (4/4)
Confidence: confirmed by the editor (5/5)
Diffusion of the vulnerable configuration: high (3/3)
Creation date: 11/08/2009
IMPACTED PRODUCTS
– Unix - plateform
DESCRIPTION OF THE VULNERABILITY
The GnuTLS library implements the SSL/TLS protocol, and the X.509
certificate handling. It is used by several software.
When a X.509 certificate contains a null character in the CN
(Common Name) or SAN (Subject Alt Name) field, GnuTLS truncates
this field. This vulnerability is similar to VIGILANCE-VUL-8908
(https://vigilance.fr/tree/1/8908), even if the vulnerable source
code is different.
An attacker can therefore invite the victim to connect to a SSL
site using a X.509 certificate with a field containing a null
character, in order to deceive the victim.
CHARACTERISTICS
Identifiers: CVE-2009-2730, GNUTLS-SA-2009-4, VIGILANCE-VUL-8935
http://vigilance.fr/vulnerability/GnuTLS-X-509-troncated-with-null-8935
