The Responsive Lightbox & Gallery plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 2.7.1. This is due to the use of strpos() for substring-based hostname validation instead of strict host comparison in the ajax_upload_image() function. This makes it possible for authenticated attackers, with Author-level access and above, to make web requests to arbitrary locations originating from the web application, which can be used to query and modify information from internal services.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Related Attack Patterns
References
- https://plugins.trac.wordpress.org/browser/responsive-lightbox/tags/2.7.0/includes/class-remote-library.php#L329
- https://plugins.trac.wordpress.org/browser/responsive-lightbox/tags/2.7.0/includes/class-remote-library.php#L344
- https://plugins.trac.wordpress.org/browser/responsive-lightbox/trunk/includes/class-remote-library.php#L329
- https://plugins.trac.wordpress.org/changeset/3464566?contextall=1
- https://www.wordfence.com/threat-intel/vulnerabilities/id/44276b28-9509-4f59-936c-fff2ae404076?source=cve