CVE-2026-42344 FastGPT: DNS rebinding TOCTOU bypass in isInternalAddress allows SSRF on all protected endpoints

FastGPT is an AI Agent building platform. In versions 4.14.11 and prior, FastGPT's isInternalAddress function in packages/service/common/system/utils.ts is vulnerable to DNS rebinding TOCTOU — Time-of-Check to Time-of-Use. The function resolves the hostname via dns.resolve4/dns.resolve6 and check...

CVE-2026-42344 FastGPT: DNS rebinding TOCTOU bypass in isInternalAddress allows SSRF on all protected endpoints

FastGPT is an AI Agent building platform. In versions 4.14.11 and prior, FastGPT's isInternalAddress function in packages/service/common/system/utils.ts is vulnerable to DNS rebinding TOCTOU — Time-of-Check to Time-of-Use. The function resolves the hostname via dns.resolve4/dns.resolve6 and check...

PT-2026-39207

Name of the Vulnerable Software and Affected Versions FastGPT versions prior to 4.14.12 Description The isInternalAddress function in packages/service/common/system/utils.ts is susceptible to DNS rebinding, a Time-of-Check to Time-of-Use TOCTOU issue. The function validates a hostname by resolvin...

FastGPT 安全漏洞

FastGPT is an open-source knowledge base question-answering system based on large language models developed by Labring. Versions of FastGPT 4.14.11 and earlier contain security vulnerabilities. These vulnerabilities stem from a DNS rebinding vulnerability in the isInternalAddress function, which...

CVE-2026-40100

CVE-2026-40100 affects FastGPT prior to version 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 is true (not the default), enabling unauthenticated SSR...

EUVD-2026-21507

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...