The Freemius SDK, as used by hundreds of WordPress plugin and theme developers, was vulnerable to Cross-Site Request Forgery and Information disclosure due to missing capability checks and nonce protection on the _get_debug_log, _get_db_option, and the _set_db_option functions in versions up to, and including 2.4.2. Any WordPress plugin or theme running a version of Freemius less than 2.4.3 is vulnerable.

The Frontend Uploader WordPress plugin through 1.3.2 does not prevent HTML files from being uploaded via its form, allowing unauthenticated user to upload a malicious HTML file containing JavaScript for example, which will be triggered when someone access the file directly

Cross-site scripting (XSS) vulnerability in the Frontend Uploader plugin 0.9.2 for WordPress allows remote attackers to inject arbitrary web script or HTML via the errors[fu-disallowed-mime-type][0][name] parameter to the default URI.