GLSA 200709-11: GDM: Local Denial of Service

http://security.gentoo.org/

Severity:	low
Title:	GDM: Local Denial of Service
Date:	09/18/2007
Bugs:	#187919
ID:	200709-11

Synopsis

GDM can be crashed by a local user, preventing it from managing future displays.

Background

GDM is the GNOME display manager.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
gnome-base/gdm	< 2.18.4	>= 2.18.4	All supported architectures

Description

The result of a g_strsplit() call is incorrectly parsed in the files daemon/gdm.c, daemon/gdmconfig.c, gui/gdmconfig.c and gui/gdmflexiserver.c, allowing for a null pointer dereference.

Impact

A local user could send a crafted message to /tmp/.gdm_socket that would trigger the null pointer dereference and crash GDM, thus preventing it from managing future displays.

Workaround

Restrict the write permissions on /tmp/.gdm_socket to trusted users only after each GDM restart.

Resolution

All GDM users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose "gnome-base/gdm"

References

CVE-2007-3381

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200709-11.xml

Concerns?

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.