Synopsis

apache, mod_ssl security update

Type/Severity

Security Advisory: Moderate

Topic

Updated httpd and mod_ssl packages that fix minor security issues in
the Apache Web server are now available for Red Hat Enterprise Linux 2.1.

Description

The Apache HTTP Server is a powerful, full-featured, efficient, and
freely-available Web server.

A buffer overflow was found in the Apache proxy module, mod_proxy, which
can be triggered by receiving an invalid Content-Length header. In order
to exploit this issue, an attacker would need an Apache installation
that was configured as a proxy to connect to a malicious site. This would
cause the Apache child processing the request to crash. The Common
Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name
CAN-2004-0492 to this issue.

On Red Hat Enterprise Linux platforms Red Hat believes this issue cannot
lead to remote code execution. This issue also does not represent a Denial
of Service attack as requests will continue to be handled by other Apache
child processes.

A stack buffer overflow was discovered in mod_ssl which can be triggered if
using the FakeBasicAuth option. If mod_ssl is sent a client certificate
with a subject DN field longer than 6000 characters, a stack overflow can
occur if FakeBasicAuth has been enabled. In order to exploit this issue
the carefully crafted malicious certificate would have to be signed by a
Certificate Authority which mod_ssl is configured to trust. The Common
Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name
CAN-2004-0488 to this issue.

This update also fixes a DNS handling bug in mod_proxy.

The mod_auth_digest module is now included in the Apache package and should
be used instead of mod_digest for sites requiring Digest authentication.

Red Hat Enterprise Linux 2.1 users of the Apache HTTP Server should upgrade
to these erratum packages, which contains Apache version 1.3.27 with
backported patches correcting 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 - 122637 - mod_proxy does reverse DNS lookups (AS2.1)
• BZ - 125704 - CAN-2004-0492 mod_proxy buffer overflow

CVEs

• CVE-2004-0492
• CVE-2004-0488

References

(none)

This erratum does not contain any packages.