vm2 Custom Module Resolver Can Bypass the External Package Allowlist by Loading a Colliding Host Package

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-2026-92951: 0.47% estimated exploitation activity in the next 30 days; percentile 40.53 (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 vm2 is a sandbox library for isolating and executing untrusted JavaScript code inside a Node.js process. It can restrict access to built-in modules and external packages. When NodeVM enables an external allowlist together with a custom resolve callback, vm2 checks the requested package name with a non-exact match. For example, if the allowlist only permits left-pad, an attacker can still bypass the check with a colliding package name such as evil-left-pad, because it contains the allowlisted name. If the colliding package already exists in a host path resolvable by the custom resolver, or if the target application's custom resolver / dependency-management workflow downloads the package and places it in a resolvable path, vm2 loads and executes that package in the host context. This lets sandboxed code bypass the module allowlist and may further lead to host code execution. Details NodeVM supports require.external to configure which external npm packages sandboxed code may…

Published by the source

1 Oct 2026, 15:37 UTC

Last modified by the source

8 Oct 2026, 13:40 UTC

Source last checked

26 Oct 2026, 13:07 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-c48m-32m9-vx93

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-c48m-32m9-vx93

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-c48m-32m9-vx93

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# Patch Next advisory brief: CVE-2026-92951

Advisory: vm2 Custom Module Resolver Can Bypass the External Package Allowlist by Loading a Colliding Host Package
IDs: CVE-2026-92951, GHSA-c48m-32m9-vx93
Record: https://patchnext.com/advisories/cve-2026-92951 (revision 3, source checked 26 Oct 2026, 13:07 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-c48m-32m9-vx93 (GitHub-reviewed advisory GHSA-c48m-32m9-vx93 lists affected ranges: npm vm2 >=0 <=3.11.6)
- Verified: https://osv.dev/vulnerability/GHSA-c48m-32m9-vx93 (OSV record GHSA-c48m-32m9-vx93 lists affected ranges: npm vm2 >=0 <3.11.7 (fixed))

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