CVE-2026-84301
FastGPT safe axios SSRF guard still allows DNS rebinding TOCTOU on protected outbound requests
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.3
FastGPT safe axios SSRF guard still allows DNS rebinding TOCTOU on protected outbound requests
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.
- Record
CVE-2026-84301- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
EUVDEUVD-2026-84559
6.3
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.
- Record
EUVD-2026-84559- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - Updated
- 2026-11-02
NVD
6.3
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.
- Record
CVE-2026-84301- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSV
6.3
FastGPT safe axios SSRF guard still allows DNS rebinding TOCTOU on protected outbound requests
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.
- Record
CVE-2026-84301- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-84301 is a medium vulnerability (CVSS 6.3) in Labring Fastgpt, published September 22, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.29%, the 21st percentile. No source names a fixed version.
References
github.com/labring/FastGPT/security/advisories/GHSA-6jwp-qf29-hpj9
github.com/labring/FastGPT/pull/7261
github.com/labring/FastGPT/commit/0a38565c9d1f790045636bd9d55f8d2296c938c7
github.com/labring/FastGPT/releases/tag/v4.15.2
github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84301.json
nvd.nist.gov/vuln/detail/CVE-2026-84301