vm2: NodeVM require.external without an explicit require.root grants unrestricted host filesystem access and full RCE

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

10.0 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-92946: 0.78% estimated exploitation activity in the next 30 days; percentile 55.84 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary NodeVM's require.external option lets sandboxed code require() local files and npm packages. When require.external is enabled and require.root is not explicitly set to a path that excludes nodemodules, two defaults combine to fully defeat the sandbox: - require.root defaults to unrestricted — "if omitted every path is allowed." - require.context defaults to "host" — files loaded this way run through the real Node.js require(), not inside any vm2 sandbox. Sandboxed code can therefore require() a relative or absolute path to vm2's own installed package (nodemodules/vm2), obtain the real, unwrapped NodeVM/VM classes, construct a brand-new unrestricted nested NodeVM instance, and execute arbitrary host OS commands via childprocess. This is exploitable using vm2's own documented "Quick Examples" configuration in README.md: root: './' reads as a safety restriction but, in any ordinary npm project layout, ./nodemodules/vm2 sits inside that same directory tree — so the restriction…

Published by the source

5 Oct 2026, 22:34 UTC

Last modified by the source

5 Oct 2026, 22:45 UTC

Source last checked

26 Oct 2026, 13:06 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-j3hm-6rg5-mchv

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-j3hm-6rg5-mchv

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-j3hm-6rg5-mchv

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# Patch Next advisory brief: CVE-2026-92946

Advisory: vm2: NodeVM `require.external` without an explicit `require.root` grants unrestricted host filesystem access and full RCE
IDs: CVE-2026-92946, GHSA-j3hm-6rg5-mchv
Record: https://patchnext.com/advisories/cve-2026-92946 (revision 3, source checked 26 Oct 2026, 13:06 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 10.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: vm2 3.11.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm vm2: affected <= 3.11.6; fixed in 3.11.7

## Suggested inspection (read-only)
- `npm ls vm2 --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on vm2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-j3hm-6rg5-mchv (GitHub-reviewed advisory GHSA-j3hm-6rg5-mchv lists affected ranges: npm vm2 >=0 <=3.11.6)
- Verified: https://osv.dev/vulnerability/GHSA-j3hm-6rg5-mchv (OSV record GHSA-j3hm-6rg5-mchv lists affected ranges: npm vm2 >=0 <3.11.7 (fixed))

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