CVE-2026-84301

Vulnerability Description

FastGPT is an open-source LLM platform for building AI applications on a knowledge base. Prior to 4.15.2, the safe Axios request interceptor in packages/service/common/api/axios.ts validates a hostname with isInternalAddress() before a later HTTP connection performs an independent DNS lookup, creating a DNS rebinding window, allowing an attacker-controlled hostname to resolve publicly during the check and to a loopback, private, link-local, or metadata address during connection. An authenticated attacker who can supply a URL to a safe-Axios-backed HTTP tool, workflow HTTP node, external file fetch, or other server-side integration can use this time-of-check/time-of-use gap to reach services that direct private-address inputs would block. The same independent re-resolution occurs after manual redirect hops because each redirect target is checked before a separate connection lookup. This issue is fixed in version 4.15.2.

CVSS Score

Related Weaknesses (CWE)

References

• https://github.com/labring/FastGPT/commit/0a38565c9d1f790045636bd9d55f8d2296c938
• https://github.com/labring/FastGPT/pull/7261
• https://github.com/labring/FastGPT/releases/tag/v4.15.2
• https://github.com/labring/FastGPT/security/advisories/GHSA-6jwp-qf29-hpj9
• https://github.com/labring/FastGPT/security/advisories/GHSA-6jwp-qf29-hpj9