Simple Machines Forum 2.1

Packages.php in Simple Machines Forum (SMF) 2.1 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via the themechanges array parameter.

LogInOut.php in Simple Machines Forum (SMF) 2.1 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via vectors related to variables derived from user input in a foreach loop.

Unrestricted file upload vulnerability in the avatar upload functionality in Simple Machines Forum before 2.0.6 and 2.1 allows remote authenticated users to execute arbitrary code by uploading a file with an executable extension, then accessing it via a direct request to the file in an unspecified directory.