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

Status: published. Published: 2026-10-30. Updated: 2026-11-02.

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.

## Remediation

- fix: flowise (npm): OSV reports a fixed version 3.1.3. Check the advisory for supported release branches. (source: OSV GHSA-9gvv-qjj3-2p6g) — https://github.com/advisories/GHSA-9gvv-qjj3-2p6g
- fix: flowise-components (npm): OSV reports a fixed version 3.1.3. Check the advisory for supported release branches. (source: OSV GHSA-9gvv-qjj3-2p6g) — https://github.com/advisories/GHSA-9gvv-qjj3-2p6g

## Affected products and versions

- FlowiseAI / Flowise (FlowiseAI/Flowise): ≥ 0; ≤ 3.1.4 (affected, semver). Source: CNA: VulnCheck
-  / flowise (flowise): ≥ 0; < 3.1.3 (affected, semver); OSV events: introduced 0; fixed 3.1.3. Source: OSV GHSA-9gvv-qjj3-2p6g
-  / flowise-components (flowise-components): ≥ 0; < 3.1.3 (affected, semver); OSV events: introduced 0; fixed 3.1.3. Source: OSV GHSA-9gvv-qjj3-2p6g

## Severity and prioritization

- CVSS 4.0: 9 (critical); 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; source: CNA: VulnCheck

- CVSS 3.1: 8.5 (high); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.32% as of 2026-11-02; percentile 24.61%

- SSVC: Not available

- Weaknesses: CWE-749

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/soovwv/cve/blob/a37354aff1e78c0601772e7716f5318c473e8640/CVE-2026-119978.md (CNA: VulnCheck; technical-description)

- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L55-L114 (CNA: VulnCheck; technical-description)

- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L1733 (CNA: VulnCheck; technical-description)

- https://github.com/advisories/GHSA-9gvv-qjj3-2p6g (CNA: VulnCheck; related)

- https://github.com/FlowiseAI/Flowise (CNA: VulnCheck; product)

- https://www.vulncheck.com/advisories/flowise-through-3.1.4-custom-function-sandbox-escape-rce-via-localfilestore (CNA: VulnCheck; third-party-advisory)

- https://github.com/advisories/GHSA-9gvv-qjj3-2p6g (OSV / GitHub Security Advisories; advisory)

- https://osv.dev/vulnerability/GHSA-9gvv-qjj3-2p6g (OSV / GitHub Security Advisories; osv)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-119978; retrieved 2026-11-02; source updated 2026-11-02

- OSV / GitHub Security Advisories: https://osv.dev/vulnerability/GHSA-9gvv-qjj3-2p6g; retrieved 2026-11-02; source updated 2026-10-31

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-119978; retrieved 2026-11-02; source updated Not reported

Revision: b8613e1593c12affa925d8895acbdfd9316dc163de18f14f558037af2dc9cde3

Canonical: https://y2.dev/cve/CVE-2026-119978

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.