RHSA-2009:1148 - Security Advisory

Topic

Updated httpd packages that fix two security issues are now available for
Red Hat Enterprise Linux 5.

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

Description

The Apache HTTP Server is a popular Web server.

A denial of service flaw was found in the Apache mod_proxy module when it
was used as a reverse proxy. A remote attacker could use this flaw to force
a proxy process to consume large amounts of CPU time. (CVE-2009-1890)

A denial of service flaw was found in the Apache mod_deflate module. This
module continued to compress large files until compression was complete,
even if the network connection that requested the content was closed before
compression completed. This would cause mod_deflate to consume large
amounts of CPU if mod_deflate was enabled for a large file. (CVE-2009-1891)

All httpd users should upgrade to these updated packages, which contain
backported patches to correct these issues. After installing the updated
packages, the httpd daemon must be restarted for the update to take effect.

Solution

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

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 i386
• Red Hat Enterprise Linux Server - AUS 5.3 x86_64
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.3 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.3 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - AUS 5.3 ia64
• Red Hat Enterprise Linux Server - AUS 5.3 i386

Fixes

• BZ - 509125 - CVE-2009-1891 httpd: possible temporary DoS (CPU consumption) in mod_deflate
• BZ - 509375 - CVE-2009-1890 httpd: mod_proxy reverse proxy DoS (infinite loop)

CVEs

• CVE-2009-1890
• CVE-2009-1891

References

• http://www.redhat.com/security/updates/classification/#important