Red Hat Application Stack RHSA-2009:1156-01 Important DoS Threat Fix

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)
A flaw was found in the handling of the "Options" and "AllowOverride" directives used by the Apache HTTP Server. In configurations using the "AllowOverride" directive with certain "Options=" arguments, local userswere not restricted from executing commands from a Server-Side-Include script as intended. (CVE-2009-1195)
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.