Check Point Advisories

GnuTLS libtasn1 ASN1 Length DER Decoding Buffer Overflow (CVE-2012-1569)

Vulnerability
Protection

Check Point Reference:	CPAI-2012-291
Date Published:	2 Jul 2012
Severity:	Critical
Last Updated:	Sunday 20 January, 2013
Source:
Industry Reference:	CVE-2012-1569
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	A buffer overflow vulnerability has been reported in libtasn1, a component of GnuTLS. The vulnerability is due to an error in the libtasn1 library while handling length fields within the ASN.1 fields. A remote attacker can exploit this vulnerability by sending specially crafted certificates to the target service. Successful exploitation would allow an attacker to execute arbitrary code in the security context of the affected service. An exploitation attempt may also cause the service to crash, resulting in a denial of service condition.

Protection Overview

This protection will detect and block attempts to exploit this vulnerability.

In order for the protection to be activated, update your Security Gateway product to the latest IPS update. For information on how to update IPS, go to SBP-2006-05, click on Protection tab and select the version of your choice.

Security Gateway R80 / R77 / R75

In the IPS tab, click Protections and find the GnuTLS libtasn1 ASN1 Length DER Decoding Buffer Overflow protection using the Search tool and Edit the protection's settings.
Install policy on all Security Gateways.

This protection's log will contain the following information:

Attack Name: SSL Protection Violation.
Attack Information: GnuTLS libtasn1 ASN1 length der decoding buffer overflow