source: https://www.securityfocus.com/bid/23611/info

LMS is prone to a remote file-include vulnerability because it fails to sufficiently sanitize user-supplied input.

Exploiting this issue may allow an attacker to compromise the application and the underlying system; other attacks are also possible.

This issue affects LMS 1.5.3 and 1.5.4; earlier versions may also be vulnerable.

http://www.example.com/modules/rtmessageadd.php?_LIB_DIR=Shell?