GLSA 200806-07: X.Org X server: Multiple vulnerabilities

http://security.gentoo.org/

Severity:	high
Title:	X.Org X server: Multiple vulnerabilities
Date:	06/19/2008
Bugs:	#225419
ID:	200806-07

Synopsis

Multiple vulnerabilities have been discovered in the X.Org X server, possibly allowing for the remote execution of arbitrary code with root privileges.

Background

The X Window System is a graphical windowing system based on a client/server model.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
x11-base/xorg-server	< 1.3.0.0-r6	>= 1.3.0.0-r6	All supported architectures

Description

Regenrecht reported multiple vulnerabilities in various X server extensions via iDefense:

The SProcSecurityGenerateAuthorization() and SProcRecordCreateContext() functions of the RECORD and Security extensions are lacking proper parameter validation (CVE-2008-1377).
An integer overflow is possible in the function ShmPutImage() of the MIT-SHM extension (CVE-2008-1379).
The RENDER extension contains several possible integer overflows in the AllocateGlyph() function (CVE-2008-2360) which could possibly lead to a heap-based buffer overflow. Further possible integer overflows have been found in the ProcRenderCreateCursor() function (CVE-2008-2361) as well as in the SProcRenderCreateLinearGradient(), SProcRenderCreateRadialGradient() and SProcRenderCreateConicalGradient() functions (CVE-2008-2362).

Impact

Exploitation of these vulnerabilities could possibly lead to the remote execution of arbitrary code with root privileges, if the server is running as root, which is the default. It is also possible to crash the server by making use of these vulnerabilities.

Workaround

It is possible to avoid these vulnerabilities by disabling the affected server extensions. Therefore edit the configuration file (/etc/X11/xorg.conf) to contain the following in the appropriate places:

      Section "Extensions"   
    	Option "MIT-SHM" "disable"
    	Option "RENDER" "disable" 
    	Option "SECURITY" "disable"
      EndSection
    
      Section "Module"
       Disable "record"
      EndSection

Resolution

All X.org X Server users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=x11-base/xorg-server-1.3.0.0-r6"

References

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200806-07.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.