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The WebP Express WordPress plugin before 0.25.16 does not escape values that its bundled HTML parser re-emits into element attributes when a non-default image delivery mode is enabled, allowing unauthenticated users to submit content that is stored and later executed as Cross-Site Scripting in the browser of any user viewing an affected page, including administrators.
The WebP Express plugin for WordPress is vulnerable to information exposure via config files in all versions up to, and including, 0.25.9. This is due to the plugin not properly randomizing the name of the config file to prevent direct access on NGINX. This makes it possible for unauthenticated attackers to extract configuration data.