CVE-2026-40100 MEDIUM

CVE-2026-40100: FastGPT has Unauthenticated SSRF in /api/core/app/mcpTools/runTool via missing CHECK_INTERNAL_IP default

Vendor Labring

Product FastGPT

Weakness CWE-918 · SSRF

Published April 10, 2026

Last update April 15, 2026

View on NVD All CVEs

CVSS base score

5.3/10

Attack vector Network

Attack complexity Low

Privileges required None

User interaction None

Confidentiality Low

Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

What the vulnerability does

01Description

FastGPT is an AI Agent building platform. Prior to 4.14.10.3, the /api/core/app/mcpTools/runTool endpoint accepts arbitrary URLs without authentication. The internal IP check in isInternalAddress() only blocks private IPs when CHECK_INTERNAL_IP=true, which is not the default. This allows unauthenticated attackers to perform SSRF against internal network resources. This vulnerability is fixed in 4.14.10.3.

Key dates

02Disclosure timeline

April 10, 2026 CVE published

April 15, 2026 Record updated

External resources

03References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2026-40100 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/918.html

Related vulnerabilities

04Related CVE

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