xtrlock Crash Screen Lock Bypass

2005-01-20T11:15:16
ID OSVDB:13098
Type osvdb
Reporter Martin Schulze(joey@infodrom.org)
Modified 2005-01-20T11:15:16

Description

Vulnerability Description

A local overflow exists in the xtrlock program. The xtrlock screen-lock program fails to buffer a long string of characters resulting in a buffer overflow. With a specially crafted request, an attacker can cause the program to crash resulting in access to the system and a loss of integrity.

Technical Description

An attacker with physical access to a console which is locked by the xtrlock program can overflow the program's buffer by holding down any key for at least a minute and pressing enter. This would crash the xtrlock program giving the attacker unauthorized access. The attacker may gain super-user privileges, as xtrlock is likely run with super-user privileges.

Solution Description

If using Debian 3.0 stable, upgrade to xtrlock version 2.0-6woody2 or higher or if using Debian 3.0 unstable, upgrade to xtrlock version version 2.0-9 or higher, as it has been reported to fix this vulnerability. An upgrade is required as there are no known workarounds.

Short Description

A local overflow exists in the xtrlock program. The xtrlock screen-lock program fails to buffer a long string of characters resulting in a buffer overflow. With a specially crafted request, an attacker can cause the program to crash resulting in access to the system and a loss of integrity.

References:

Vendor Specific Solution URL: http://security.debian.org/pool/updates/main/x/xtrlock/ Vendor Specific News/Changelog Entry: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=278191 Vendor Specific News/Changelog Entry: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=278190 Security Tracker: 1012909 Security Tracker: 1012954 Secunia Advisory ID:13938 Other Advisory URL: http://www.debian.org/security/2005/dsa-649 ISS X-Force ID: 18991 CVE-2005-0079 Bugtraq ID: 12316