The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers via a malformed URI containing an initial @ (at sign) character.

modules/arch/win32/mod_isapi.c in mod_isapi in the Apache HTTP Server 2.0.37 through 2.0.63, 2.2.0 through 2.2.14, and 2.3.x before 2.3.7, when running on Windows, does not ensure that request processing is complete before calling isapi_unload for an ISAPI .dll module, which allows remote attackers to execute arbitrary code via unspecified vectors related to a crafted request, a reset packet, and "orphaned callback pointers."

The ap_proxy_ajp_request function in mod_proxy_ajp.c in mod_proxy_ajp in the Apache HTTP Server 2.2.x before 2.2.15 does not properly handle certain situations in which a client sends no request body, which allows remote attackers to cause a denial of service (backend server outage) via a crafted request, related to use of a 500 error code instead of the appropriate 400 error code.

The Apache HTTP Server 2.2.11 and earlier 2.2 versions does not properly handle Options=IncludesNOEXEC in the AllowOverride directive, which allows local users to gain privileges by configuring (1) Options Includes, (2) Options +Includes, or (3) Options +IncludesNOEXEC in a .htaccess file, and then inserting an exec element in a .shtml file.

Cross-site request forgery (CSRF) vulnerability in the balancer-manager in mod_proxy_balancer for Apache HTTP Server 2.2.x allows remote attackers to gain privileges via unspecified vectors.