Inline Image Upload for BBPress <= 1.1.19 - Authenticated (Subscriber+) Arbitrary File Upload

The Inline Image Upload for BBPress plugin for WordPress is vulnerable to arbitrary file uploads due to missing file extension validation in the file uploading functionality in all versions up to, and including, 1.1.19. This makes it possible for authenticated attackers, with Subscriber-level access and above, to upload arbitrary files on the affected site's server which may make remote code execution possible. This may be exploitable by unauthenticated attackers when the "Allow guest users without accounts to create topics and replies" setting is enabled.