Tree Sitemap < 2.9 - Arbitrary Plugin Installation/Activation via Low Privilege User

Low privileged users can use the AJAX action 'cp_plugins_do_button_job_later_callback' in the Tree Sitemap WordPress plugin before 2.9, to install any plugin (including a specific version) from the WordPress repository, as well as activate arbitrary plugin from then blog, which helps attackers install vulnerable plugins and could lead to more critical vulnerabilities like RCE.