The PHP interpreter is a heavy-duty CGI EXE (or SAPI module, depending on configuration) that implements an HTML-embedded script language. A vulnerability in PHP can be used to cause a denial of service in some cases. PHP's install process on Apache requires a "/php/" alias to be created, as it resolves CGI paths to a virtual. (e.g, /php/php.exe not C:\php\php.exe). To solve the obvious security vulnerability posed by allowing PHP to run from the web, the development team added a cgi.force_redirect option that is enabled by default in Apache. However, regardless of the force_redirect value, it is still possible to load the binary without a script path: (e.g, http://localhost/php/php) A problem exists in PHP; specifically, it does not terminate when given no command-line arguments. A consistent flow of requests like the above will exhaust all resources for CGI/ASAPI on the server. Exploit: http://www.murphy.101main.net/php-apache.c I tried to make sure this would run on Linux/BSD, but no guarantees... Compiles cleanly on WinMe with MSVC 6.0.
