FastGPT allows attackers to call any plugin endpoint under /api/plugin/ without authentication when running versions 4.14.0 through 4.14.5. This lack of authentication can cause the plugin system to crash or lose its installation state, leading to a denial‑of‑service on the platform. The vulnerability does not expose sensitive data or credentials, but it compromises the availability of the plugin feature and may affect the stability of the overall system.

The affected product is the FastGPT AI Agent building platform from labring. Versions 4.14.0 up to and including 4.14.5 are vulnerable. The latest release, 4.14.5‑fix, contains the remedy. Versions earlier than 4.14.0 exhibit only read‑only plugin interfaces, so the impact is minor for those earlier releases.

The CVSS score of 6.9 signals a moderate severity, and the EPSS score of less than 1% indicates a low probability of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog, suggesting no proven widespread use. Attackers can exploit the flaw merely by sending unauthenticated HTTP requests to the exposed plugin endpoints, without needing any special privileges or prior access. Because the flaw directly crashes the plugin subsystem, the primary risk to the platform is a denial of service rather than data theft.