The Note You're Voting On
New York PHP ¶18 years ago
Warning: $_SERVER['PHP_SELF'] can include arbitrary user input. The documentation should be updated to reflect this.
The request "http://example.com/info.php/attack%20here" will run /info.php, but in Apache $_SERVER['PHP_SELF'] will equal "/info.php/attack here". This is a feature, but it means that PHP_SELF must be treated as user input.
The attack string could contain urlencoded HTML and JavaScript (cross-site scripting) or it could contain urlencoded linebreaks (HTTP response-splitting).
The use of $_SERVER['SCRIPT_NAME'] is recommended instead.