The WP Compress – Instant Performance & Speed Optimization plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the ‘custom_server’ parameter in all versions up to, and including, 6.30.03 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

The WP Compress – Image Optimizer [All-In-One] plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the several functions in versions up to, and including, 6.20.01. This makes it possible for authenticated attackers, with subscriber-level permissions and above, to edit plugin settings, including storing cross-site scripting, in multisite environments.

The WP Compress – Image Optimizer [All-In-One plugin for WordPress is vulnerable to Open Redirect in all versions up to, and including, 6.20.01. This is due to insufficient validation on the redirect url supplied via the 'css' parameter. This makes it possible for unauthenticated attackers to redirect users to potentially malicious sites if they can successfully trick them into performing an action.

The WP Compress – Image Optimizer plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the 'wps_local_compress::__construct' function in all versions up to, and including, 6.11.10. This makes it possible for unauthenticated attackers to reset the CDN region and set a malicious URL to deliver images.