The GPTranslate – Multilingual AI Translation for WordPress: Automatically Translate Websites plugin for WordPress is vulnerable to Stored Cross-Site Scripting via REST API Translation Storage in all versions up to, and including, 2.31 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The deterministically derived API key (sha256 of the site URL) is printed in the HTML source of every page via the JavaScript variable gptApiKey, meaning any unauthenticated visitor can retrieve the key and submit malicious translation payloads to the /wp-json/gptranslate/v1/request endpoint without any additional precondition.