CVE-2026-91931

9.0 criticalEPSS 0.7%

Critical (9.0). EPSS 0.7% chance of exploitation in the next 30 days.

Flowise before 3.1.4 contains a remote code execution vulnerability in the Custom MCP node that allows authenticated attackers to execute arbitrary code by supplying npx package names in the mcpServerConfig parameter. Attackers can invoke npx with attacker-controlled npm packages to execute code on the Flowise server.

Severity

CVSS 4.0

9.0 critical

CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CVSS 3.1

8.5 high

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

EPSS: 0.7% chance of exploitation in the next 30 days; higher than 52% of CVEs (scores of 2026-10-31)
CWE: CWE-78
Published: 2026-09-15
Modified: 2026-09-23
Record from: the NVD, synced 2026-10-19

References

https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-vcwp-f9rq-3887
https://www.vulncheck.com/advisories/flowise-before-3.1.4-remote-code-execution-via-custom-mcp-npx
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-vcwp-f9rq-3887

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