RHSA-2003:289 - Security Advisory

Topic

Updated XFree86 packages provide security fixes to font libraries and XDM.

Description

XFree86 is an implementation of the X Window System providing the core
graphical user interface and video drivers. XDM is the X display manager.

Multiple integer overflows in the transfer and enumeration of font
libraries in XFree86 allow local or remote attackers to cause a denial of
service or execute arbitrary code via heap-based and stack-based buffer
overflow attacks. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2003-0730 to this issue.

The risk to users from this vulnerability is limited because only clients
can be affected by these bugs, however in some (non-default)
configurations, both xfs and the X Server can act as clients
to remote font servers.

XDM does not verify whether the pam_setcred function call succeeds, which
may allow attackers to gain root privileges by triggering error conditions
within PAM modules, as demonstrated in certain configurations of the
pam_krb5 module. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2003-0690 to this issue.

Users are advised to upgrade to these updated XFree86 4.1.0 packages, which
contain backported security patches and are not vulnerable to these issues.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

To update all RPMs for your particular architecture, run:

rpm -Fvh [filenames]

where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains the
desired RPMs.

Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

If up2date fails to connect to Red Hat Network due to SSL Certificate
Errors, you need to install a version of the up2date client with an updated
certificate. The latest version of up2date is available from the Red Hat
FTP site and may also be downloaded directly from the RHN website:

https://rhn.redhat.com/help/latest-up2date.pxt

Affected Products

• Red Hat Enterprise Linux Server 2 ia64
• Red Hat Enterprise Linux Server 2 i386
• Red Hat Enterprise Linux Workstation 2 ia64
• Red Hat Enterprise Linux Workstation 2 i386

Fixes

• BZ - 104647 - CAN-2003-0730 font lib XFree86 integer overflows
• BZ - 104648 - CAN-2003-0690 xdm pam_setcred vulnerability

CVEs

• CVE-2003-0730

References

(none)