The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress contains a stored XSS vulnerability (CWE-79) via the form's subject parameter in all versions up to 5.2.6. This vulnerability is due to improper neutralization of input during web page generation, allowing unauthenticated attackers to inject arbitrary web scripts that execute when users access the injected pages. The CVSS 3.1 base score is 7.2, reflecting network attack vector, low attack complexity, no privileges required, no user interaction, and impacts on confidentiality and integrity with scope changed.

Successful exploitation allows unauthenticated attackers to inject and execute arbitrary scripts in the context of affected users, potentially leading to theft of sensitive information or session hijacking. The vulnerability impacts confidentiality and integrity but does not affect availability. There are no known exploits in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should consider disabling or restricting access to the vulnerable plugin functionality or applying manual input sanitization and output escaping if feasible. Monitor vendor channels for updates and apply patches promptly once available.