PHP for Windows, when installed on Apache 2.0.28 beta as a standalone CGI module, allows remote attackers to obtain the physical path of the php.exe via a request with malformed arguments such as /123, which leaks the pathname in the error message.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2002-0246
http://www.securityfocus.com/bid/4056