The Apache Software Foundation and the Apache HTTP Server Project are
   pleased to announce the release of version 2.2.21 of the Apache HTTP
   Server ("Apache").  This version of Apache is principally a security
   and bug fix release:

     * SECURITY: CVE-2011-3348 (cve.mitre.org)
       mod_proxy_ajp when combined with mod_proxy_balancer: Prevents
       unrecognized HTTP methods from marking ajp: balancer members
       in an error state, avoiding denial of service.

     * SECURITY: CVE-2011-3192 (cve.mitre.org)
       core: Further fixes to the handling of byte-range requests to use
       less memory, to avoid denial of service. This patch includes fixes
       to the patch introduced in release 2.2.20 for protocol compliance,
       as well as the MaxRanges directive.

   Note the further advisories on the state of CVE-2011-3192 will no longer
   be broadcast, but will be kept up to date at;

     http://httpd.apache.org/security/CVE-2011-3192.txt

   We consider this release to be the best version of Apache available, and
   encourage users of all prior versions to upgrade.

   Apache HTTP Server 2.2.21 is available for download from:

     http://httpd.apache.org/download.cgi

   Please see the CHANGES_2.2 file, linked from the download page, for a
   full list of changes.  A condensed list, CHANGES_2.2.21 provides the
   complete list of changes since 2.2.19.  A summary of all of the security
   vulnerabilities addressed in this and earlier releases is available:

     http://httpd.apache.org/security/vulnerabilities_22.html

   This release includes the Apache Portable Runtime (APR) version 1.4.5
   and APR Utility Library (APR-util) version 1.3.12, bundled with the tar
   and zip distributions.  The APR libraries libapr and libaprutil (and
   on Win32, libapriconv version 1.2.1) must all be updated to ensure
   binary compatibility and address many known security and platform bugs.

   Apache 2.2 offers numerous enhancements, improvements, and performance
   boosts over the 2.0 codebase.  For an overview of new features
   introduced since 2.0 please see:

     http://httpd.apache.org/docs/2.2/new_features_2_2.html

   This release builds on and extends the Apache 2.0 API.  Modules written
   for Apache 2.0 will need to be recompiled in order to run with Apache
   2.2, and require minimal or no source code changes.

     http://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x/VERSIONING

   When upgrading or installing this version of Apache, please bear in mind
   that if you intend to use Apache with one of the threaded MPMs (other
   than the Prefork MPM), you must ensure that any modules you will be
   using (and the libraries they depend on) are thread-safe.