CVE-2026-40100: FastGPT has Unauthenticated SSRF in /api/core/app/mcpTools/runTool via missing CHECK_INTERNAL_IP default
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 CHECKINTERNALIP=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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-40100?
CVE-2026-40100 has a high severity rating due to its potential for unauthorized access via SSRF.
How do I fix CVE-2026-40100?
To fix CVE-2026-40100, upgrade FastGPT to version 4.14.10.4 or later, which includes a proper internal IP address check.
What impact does CVE-2026-40100 have on my system?
CVE-2026-40100 allows unauthenticated users to access potentially sensitive internal resources through arbitrary URL requests.
Which versions of FastGPT are affected by CVE-2026-40100?
CVE-2026-40100 affects FastGPT versions prior to 4.14.10.4.
Is authentication required for the /api/core/app/mcpTools/runTool endpoint in CVE-2026-40100?
No, the /api/core/app/mcpTools/runTool endpoint does not require authentication in the affected versions of FastGPT.