source: http://www.securityfocus.com/bid/59470/info

The WP Super Cache plugin for WordPress is prone to a remote PHP code-execution vulnerability.

An attacker can exploit this issue to execute arbitrary PHP code within the context of the web server.

WP Super Cache 1.2 is vulnerable; other versions may also be affected. 

<!?mfunc echo PHP_VERSION; ?><!?/mfunc?>