Vulnerability · Published Oct 30, 2026 · Assigned by VulnCheck

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

High 8.5

In plain English

A high-severity security flaw in Flowise from FlowiseAI. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.5High

Exploit odds (30 days)0.3%top 72.7% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	flowise	3.1.3	GHSA-9gvv-qjj3-2p6g
npm	flowise-components	3.1.3	GHSA-9gvv-qjj3-2p6g

Affected products (as reported)

Vendor	Product	Versions
FlowiseAI	Flowise	0 – through 3.1.4

Weakness: CWE-749 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

References

Researcher write-up technical-description
https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L55-L114 technical-description
https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L1733 technical-description
GitHub Security Advisory (GHSA-9gvv-qjj3-2p6g) related
https://github.com/FlowiseAI/Flowise product
VulnCheck Advisory: Flowise through 3.1.4 Custom Function Sandbox Escape RCE via LocalFileStore third-party-advisory