How severe is CVE-2026-40100?

CVE-2026-40100 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-40100 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40100?

CVE-2026-40100 affects Fastgpt. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-40100?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-40100 have an EU (EUVD) identifier?

Yes. CVE-2026-40100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21507.

When was CVE-2026-40100 published?

CVE-2026-40100 was published on 2026-04-10 and last updated on 2026-06-17.

CVE-2026-40100

CVE-2026-40100 is a medium-severity vulnerability in Fastgpt with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-918.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21507
Weakness: CWE-918
Affected product: Fastgpt
Published: 2026-04-10
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-40100?: 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.
How severe is CVE-2026-40100?: CVE-2026-40100 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-40100 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40100?: CVE-2026-40100 affects Fastgpt. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-40100?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40100 have an EU (EUVD) identifier?: Yes. CVE-2026-40100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21507.
When was CVE-2026-40100 published?: CVE-2026-40100 was published on 2026-04-10 and last updated on 2026-06-17.

References

https://github.com/labring/FastGPT/security/advisories/GHSA-jrhc-f3j7-f8g4

Affected products (1)

cpe:2.3:a:fastgpt:fastgpt:*:*:*:*:*:*:*:*

More vulnerabilities in Fastgpt

CVE-2026-34162 — Critical (CVSS 10.0): FastGPT is an AI Agent building platform. Prior to version 4.14.9.5, the FastGPT HTTP tools testing endpoint…
CVE-2026-40351 — Critical (CVSS 9.8): FastGPT is an AI Agent building platform. In versions prior to 4.14.9.5, the password-based login endpoint uses…
CVE-2026-40352 — High (CVSS 8.8): FastGPT is an AI Agent building platform. In versions prior to 4.14.9.5, the password change endpoint is vulnerable to…
CVE-2026-33075 — High (CVSS 8.8): FastGPT is an AI Agent building platform. In versions 4.14.8.3 and below, the fastgpt-preview-image.yml workflow is…
CVE-2026-40252 — High (CVSS 8.1): FastGPT is an AI Agent building platform. Prior to 4.14.10.4, Broken Access Control vulnerability (IDOR/BOLA) allows…
CVE-2026-34163 — High (CVSS 7.7): FastGPT is an AI Agent building platform. Prior to version 4.14.9.5, FastGPT's MCP (Model Context Protocol) tools…

All CVEs affecting Fastgpt →

Other CWE-918 (Server-Side Request Forgery (SSRF)) vulnerabilities

CVE-2026-47938 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) versions 7.4.3 build 9394 and earlier are affected by a Server-Side Request Forgery (SSRF)…
CVE-2026-35431 — Critical (CVSS 10.0): Server-side request forgery (ssrf) in Microsoft Entra ID Entitlement Management allows an unauthorized attacker to…
CVE-2026-32186 — Critical (CVSS 10.0): Server-side request forgery (ssrf) in Microsoft Bing allows an unauthorized attacker to elevate privileges over a…
CVE-2026-33107 — Critical (CVSS 10.0): Server-side request forgery (ssrf) in Azure Databricks allows an unauthorized attacker to elevate privileges over a…
CVE-2026-32871 — Critical (CVSS 10.0): FastMCP is a Pythonic way to build MCP servers and clients. Prior to version 3.2.0, the OpenAPIProvider in FastMCP…
CVE-2026-32169 — Critical (CVSS 10.0): Server-side request forgery (ssrf) in Azure Cloud Shell allows an unauthorized attacker to elevate privileges over a…

Browse all CWE-918 (Server-Side Request Forgery (SSRF)) vulnerabilities →