CVE-2026-119978
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 9.0 CRITICALCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.34% probability · 27th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-749
- Source
- disclosure@vulncheck.com
EPSS moved from 0.3% on 31 October 2026 to 0.3% on 3 November 2026.
References
- https://github.com/FlowiseAI/Flowise
- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L1733
- https://github.com/FlowiseAI/Flowise/blob/a65f81bb43ef66d3ce734bf0dff4223ae8041c95/packages/components/src/utils.ts#L55-L114
- https://github.com/advisories/GHSA-9gvv-qjj3-2p6g
- https://github.com/soovwv/cve/blob/a37354aff1e78c0601772e7716f5318c473e8640/CVE-2026-119978.md
- https://www.vulncheck.com/advisories/flowise-through-3.1.4-custom-function-sandbox-escape-rce-via-localfilestore
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.