HighVulnerability

CVE-2026-119978: Flowise sandbox escape to OS command execution via node-custom-function endpoint

Source: NVD(opens in a new tab)
Identifier: CVE-2026-119978
Published: October 30, 2026
Record updated: October 30, 2026

Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.

Summary

Flowise through 3.1.4 has a sandbox escape (CVE-2026-119978) that lets authenticated users run OS commands when ALLOW_BUILTIN_DEP=true. Attackers submit JavaScript to /api/v1/node-custom-function that uses LocalFileStore to write a file into the mammoth package and then require it, escaping vm2 as the Flowise process user.

Mitigation

The source does not state a fix yet. Check the original advisory for updates.

Details

Scores and exploitation

CVSS score: 8.5(high)
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector: network
Attack complexity: high
Privileges required: low
User interaction: none
EPSS: Not scored. FIRST had not published an EPSS score for this CVE when it was last checked on October 30, 2026.
Disclosure date: October 30, 2026

Weaknesses and techniques

Weakness (CWE): CWE-749

Classification

Attack type: Other
Attack sophistication: Moderate
AI component targeted: Plugin
Impact: Confidentiality,
Integrity,
Availability
Labels: security

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative. The source gives this advisory a description and no title, so the title above is a headline generated from the source text.

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-119978

First tracked: October 30, 2026 at 08:09 PM ET, from NVD/CVE Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 90% (self-assessed)

Summary

Mitigation

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