vm2: NodeVM node:-prefixed negative builtin deny bypass exposes child_process

Exploitation

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

CVSS

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

EPSS

• CVE-2026-92957: 0.54% estimated exploitation activity in the next 30 days; percentile 45.28 (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 normalizes node:-prefixed builtin specifiers during require() resolution, but it does not normalize user-provided negative builtin entries in wildcard policy. As a result, this configuration: does not deny the canonical childprocess builtin. Sandboxed code can require both childprocess and node:childprocess, and receives the host module with process-spawning APIs such as execSync and spawn. The safe proof below only checks module and function reachability. It does not execute any OS command. Affected Mode NodeVM. Affected Configuration This affects users who deny builtins using their node:-prefixed spelling, expecting -node:childprocess to deny require('node:childprocess') and require('childprocess'). Affected Files / Functions - lib/builtin.js - makeBuiltinsFromLegacyOptions - wildcard builtin expansion - exact negative entry check: builtins.indexOf(\-${name}\) - addDefaultBuiltin - lib/resolver.js - Resolver.resolve - lib/setup-node-sandbox.js - requireImpl - node:…

Published by the source

1 Oct 2026, 15:36 UTC

Last modified by the source

1 Oct 2026, 15:45 UTC

Source last checked

26 Oct 2026, 13:06 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-8686-vhfx-7r3j

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-8686-vhfx-7r3j

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-8686-vhfx-7r3j

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# Patch Next advisory brief: CVE-2026-92957

Advisory: vm2: NodeVM node:-prefixed negative builtin deny bypass exposes child_process
IDs: CVE-2026-92957, GHSA-8686-vhfx-7r3j
Record: https://patchnext.com/advisories/cve-2026-92957 (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 9.9)
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-8686-vhfx-7r3j (GitHub-reviewed advisory GHSA-8686-vhfx-7r3j lists affected ranges: npm vm2 >=0 <=3.11.6)
- Verified: https://osv.dev/vulnerability/GHSA-8686-vhfx-7r3j (OSV record GHSA-8686-vhfx-7r3j lists affected ranges: npm vm2 >=0 <3.11.7 (fixed))

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