The Red Hat build script for the GNOME Display Manager (GDM) before 2.16.0-56 on Red Hat Enterprise Linux (RHEL) 5 omits TCP Wrapper support, which might allow remote attackers to bypass intended access restrictions via XDMCP connections, a different vulnerability than CVE-2007-5079.

The remote Oracle Linux 5 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2009-1364 advisory.

    [1:2.16.0-56]
    - Resolves: #239818 181302
    - Fix tcp wrappers detection on 64-bit

    [1:2.16.0-55]     Resolves: #196054
    - Fix docs subpackage Requires

    [1:2.16.0-53]     Resolves: #196054
    - Add docs subpackage

    [1:2.16.0-52]     Resolves: #226931
    - Add te_IN translations

    [1:2.16.0-51]     Resolves: #441971
    - Make ctrl-alt-backspace at the login screen more robust

    [1:2.16.0-50]     Resolves: #458331
    - Add GDM to audio group by default.

    [1:2.16.0-49]     Resolves: #474588
    - Don't crash if defined extended input device is unplugged       Patch by Olivier Fourdan.

    [1:2.16.0-48]     Resolves: #239818
    - Rebuild with tcp_wrappers build requires

    [1:2.16.0-47]     Resolves: #473262
    - Fix pointer on tablet devices.

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

CVE-2009-2697 gdm not built with tcp_wrappers

A flaw was found in the way the gdm package was built. The gdm package was missing TCP wrappers support, which could result in an administrator believing they had access restrictions enabled when they did not. (CVE-2009-2697)

This update also fixes the following bugs :

  - the GDM Reference Manual is now included with the gdm     packages. The gdm-docs package installs this document in     HTML format in '/usr/share/doc/'. (BZ#196054)

  - GDM appeared in English on systems using Telugu (te_IN).
    With this update, GDM has been localized in te_IN.
    (BZ#226931)

  - the Ctrl+Alt+Backspace sequence resets the X server when     in runlevel 5. In previous releases, however, repeated     use of this sequence prevented GDM from starting the X     server as part of the reset process. This was because     GDM sometimes did not notice the X server shutdown     properly and would subsequently fail to complete the     reset process. This update contains an added check to     explicitly notify GDM whenever the X server is     terminated, ensuring that resets are executed reliably.
    (BZ#441971)

  - the 'gdm' user is now part of the 'audio' group by     default. This enables audio support at the login screen.
    (BZ#458331)

  - the gui/modules/dwellmouselistener.c source code     contained incorrect XInput code that prevented tablet     devices from working properly. This update removes the     errant code, ensuring that tablet devices work as     expected. (BZ#473262)

  - a bug in the XOpenDevice() function prevented the X     server from starting whenever a device defined in     '/etc/X11/xorg.conf' was not actually plugged in. This     update wraps XOpenDevice() in the gdk_error_trap_pop()     and gdk_error_trap_push() functions, which resolves this     bug. This ensures that the X server can start properly     even when devices defined in '/etc/X11/xorg.conf' are     not plugged in. (BZ#474588)

GDM must be restarted for this update to take effect. Rebooting achieves this, but changing the runlevel from 5 to 3 and back to 5 also restarts GDM.

Note: setup needed to be updated for dependencies.

Updated gdm packages that fix a security issue and several bugs are now available for Red Hat Enterprise Linux 5.

This update has been rated as having low security impact by the Red Hat Security Response Team.

The GNOME Display Manager (GDM) is a configurable re-implementation of XDM, the X Display Manager. GDM allows you to log in to your system with the X Window System running, and supports running several different X sessions on your local machine at the same time.

A flaw was found in the way the gdm package was built. The gdm package was missing TCP wrappers support, which could result in an administrator believing they had access restrictions enabled when they did not. (CVE-2009-2697)

This update also fixes the following bugs :

* the GDM Reference Manual is now included with the gdm packages. The gdm-docs package installs this document in HTML format in '/usr/share/doc/'. (BZ#196054)

* GDM appeared in English on systems using Telugu (te_IN). With this update, GDM has been localized in te_IN. (BZ#226931)

* the Ctrl+Alt+Backspace sequence resets the X server when in runlevel 5. In previous releases, however, repeated use of this sequence prevented GDM from starting the X server as part of the reset process.
This was because GDM sometimes did not notice the X server shutdown properly and would subsequently fail to complete the reset process.
This update contains an added check to explicitly notify GDM whenever the X server is terminated, ensuring that resets are executed reliably. (BZ#441971)

* the 'gdm' user is now part of the 'audio' group by default. This enables audio support at the login screen. (BZ#458331)

* the gui/modules/dwellmouselistener.c source code contained incorrect XInput code that prevented tablet devices from working properly. This update removes the errant code, ensuring that tablet devices work as expected. (BZ#473262)

* a bug in the XOpenDevice() function prevented the X server from starting whenever a device defined in '/etc/X11/xorg.conf' was not actually plugged in. This update wraps XOpenDevice() in the gdk_error_trap_pop() and gdk_error_trap_push() functions, which resolves this bug. This ensures that the X server can start properly even when devices defined in '/etc/X11/xorg.conf' are not plugged in.
(BZ#474588)

All users should upgrade to these updated packages, which resolve these issues. GDM must be restarted for this update to take effect.
Rebooting achieves this, but changing the runlevel from 5 to 3 and back to 5 also restarts GDM.

ID	Name	Product	Family	Severity
181105	Oracle Linux 5 : gdm (ELSA-2009-1364)	Nessus	Oracle Linux Local Security Checks	critical
60652	Scientific Linux Security Update : gdm on SL5.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	medium
43789	CentOS 5 : gdm (CESA-2009:1364)	Nessus	CentOS Local Security Checks	medium
40840	RHEL 5 : gdm (RHSA-2009:1364)	Nessus	Red Hat Local Security Checks	medium

Detections

Analytics

CVE-2009-2697

critical

Tenable Plugins

critical

medium

medium

medium