source: https://www.securityfocus.com/bid/47309/info eForum is prone to an arbitrary-file-upload vulnerability because the application fails to adequately sanitize user-supplied input. An attacker can exploit this issue to upload arbitrary code and run it in the context of the webserver process. eForum 1.1 is vulnerable; other versions may also be affected. if (isset($_FILES)) { //upload attachments ...snip... $invalidFileTypes = array('php', 'php3', 'php4', 'php5', 'exe', 'dll', 'so', 'htaccess'); $uploaddir = $eforum->path.'/upload'; $upfiles = $_FILES['efattachment']; foreach ($upfiles['name'] as $idx => $upname) { if ($upname != '') { $source = $upfiles['tmp_name'][$idx]; if (is_uploaded_file($source)) { if (in_array($fmanager->FileExt($upname), $invalidFileTypes)) { continue; }