ShortPixel Adaptive Images <= 3.11.5 - Missing Authorization to Authenticated (Subscriber+) Third-Party Plugin Option Modification via 'causer' Parameter

The ShortPixel Adaptive Images – WebP, AVIF, CDN, Image Optimization plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 3.11.5. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with subscriber-level access and above, to modify configuration options of third-party plugins including ShortPixel Image Optimizer, Autoptimize, WP Rocket, Imagify, and LiteSpeed Cache, as well as the plugin's own API key and account binding. Exploitation requires the respective third-party plugins to be installed, as the impact against those plugins' settings is only reachable when those plugins are present.