The Solace Extra WordPress plugin before 1.6.1 does not perform capability or nonce checks in one of its AJAX actions, allowing any authenticated user such as a subscriber (and, via CSRF, any logged-in user) to update post meta on arbitrary posts and to deactivate the site's active templates.
https://wpscan.com/vulnerability/514f4577-1f7e-4d50-90d5-36bc504a260c/