The Apache Portable Runtime is a portability library used by the Apache HTTP Server and other projects. It provides a free library of C data structures and routines. The fix for CVE-2011-0419 introduced an infinite loop flaw in the apr_fnmatch function when the APR_FNM_PATHNAME matching flag was used. A remote attacker could possibly use this flaw to cause a denial of service on an application using the apr_fnmatch function. Note: This problem affected httpd configurations using the Location directive with wildcard URLs. The denial of service could have been triggered during normal operation; it did not specifically require a malicious HTTP request. This update also addresses additional problems introduced by the rewrite of the apr_fnmatch function, which was necessary to address the CVE-2011-0419 flaw. All apr users should upgrade to these updated packages, which contain a backported patch to correct this issue. Applications using the apr library, such as httpd, must be restarted for this update to take effect.