RCE in Flowiseai Flowise
CVE-2026-91931
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.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.007 (52.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 52.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/FlowiseAI/Flowise/security/advisories/GHSA-vcwp-f9rq-3887 (vendor-advisory)
- www.vulncheck.com/advisories/flowise-before-3.1.4-remote-code-execution-via-cus… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-91931?
- CVE-2026-91931 is a high-severity vulnerability in Flowiseai Flowise, classified under OS Command Injection. CVSS score: 8.5/10. Published 2026-09-15.
- How severe is CVE-2026-91931?
- High severity. CVSS v3 base score is 8.5 out of 10.