Vigil@nce - OpenVPN: denial of service via tls-authenticated
December 2014 by Vigil@nce
This bulletin was written by Vigil@nce : http://vigilance.fr/offer
SYNTHESIS OF THE VULNERABILITY
An authenticated attacker can send a malicious message in
tls-authenticated mode of OpenVPN, in order to trigger a denial of
service.
Impacted products: Debian, Fedora, MBS, openSUSE, Slackware, SUSE
Linux Enterprise Desktop, SLES, Ubuntu, Unix (platform)
Severity: 2/4
Creation date: 02/12/2014
DESCRIPTION OF THE VULNERABILITY
The OpenVPN product offers a tls-authenticated mode using X.509
certificates.
However, if a control message has a length shorter than 4 bytes,
an assertion error occurs in the key_method_2_read() function of
the src/openvpn/ssl.c file.
An authenticated attacker can therefore send a malicious message
in tls-authenticated mode of OpenVPN, in order to trigger a denial
of service.
ACCESS TO THE COMPLETE VIGIL@NCE BULLETIN
http://vigilance.fr/vulnerability/OpenVPN-denial-of-service-via-tls-authenticated-15730