Improper neutralization of Server-Side Includes (SSW) within a web page in Movable Type series allows a remote authenticated attacker with Privilege of 'Manage of Content Types' may execute an arbitrary Perl script and/or an arbitrary OS command. Affected products/versions are as follows: Movable Type 7 r.5301 and earlier (Movable Type 7 Series), Movable Type Advanced 7 r.5301 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.53 and earlier, and Movable Type Premium Advanced 1.53 and earlier.