Theme Editor <= 2.8 - Authenticated (Admin+) PHAR Deserialization

Vulnerability Description

The Theme Editor plugin for WordPress is vulnerable to deserialization of untrusted input via the 'images_array' parameter in versions up to, and including 2.8. This makes it possible for authenticated attackers with administrative privileges to call files using a PHAR wrapper that will deserialize and call arbitrary PHP Objects that can be used to perform a variety of malicious actions granted a POP chain is also present. It also requires that the attacker is successful in uploading a file with the serialized payload.

References

• https://www.wordfence.com/threat-intel/vulnerabilities/id/88fe46bf-8e85-4550-92ad-bdd426e5a745?source=cve
• https://plugins.trac.wordpress.org/browser/theme-editor/trunk/ms_child_theme_editor.php#L495
• https://plugins.trac.wordpress.org/changeset/3142694/