manageuser.php in Collabtive before 0.7.6 allows remote authenticated users, and possibly unauthenticated attackers, to bypass intended access restrictions and…

manageuser.php in Collabtive before 0.7.6 allows remote authenticated users, and possibly unauthenticated attackers, to bypass intended access restrictions and upload and execute arbitrary files by uploading an avatar file with an accepted Content-Type such as image/jpeg, then accessing it via a direct request to the file in files/standard/avatar.