CVE-2026-40933: Flowise Authenticated RCE via MCP Adapters

# CVE-2026-40933: Flowise Authenticated RCE via MCP Adapters

https://gcdradar.vercel.app/incidents/cve-2026-40933-flowise-authenticated-rce-via-mcp-adapters · AIR-2026-0570 · closed 2026-04-16

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-04-16
- AI role: Attack on AI
- Products: Flowise
- CVE ids: CVE-2026-40933
- CVSS: 9.9

## Summary

An insecure serialization flaw in Flowise allows authenticated users to execute arbitrary commands through MCP stdio server configurations. A patch has been provided to address the issue.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-04-21: CVE-2026-40933: Flowise is a drag & drop user interface to build a customized large language model flow. (https://nvd.nist.gov/vuln/detail/CVE-2026-40933)
- 2026-04-16: CVE-2026-40933: Flowise: Authenticated RCE Via MCP Adapters (https://github.com/advisories/GHSA-c9gw-hvqq-f33r)

## Sources

- 2026-04-16 GitHub Advisory Database: CVE-2026-40933: Flowise: Authenticated RCE Via MCP Adapters https://github.com/advisories/GHSA-c9gw-hvqq-f33r
- 2026-04-21 NVD: CVE-2026-40933: Flowise is a drag & drop user interface to build a customized large language model flow. https://nvd.nist.gov/vuln/detail/CVE-2026-40933

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.