---
id: GHSA-c9wr-qm7p-p6vc
title: >-
  Duplicate Advisory: vm2: NodeVM custom resolution bypasses external path
  boundaries
summary: >-
  Duplicate Advisory: vm2: NodeVM custom resolution bypasses external path
  boundaries
severity: critical
cvss: 9
cwe:
  - CWE-863
vendor: vm2
product: vm2
ecosystem: npm
affected:
  - vm2 < 3.12.2
patched:
  - vm2 3.12.2
published: '2026-09-27'
updated: '2026-10-05'
sourceUpdated: '2026-10-05T23:23:52Z'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-c9wr-qm7p-p6vc'
references:
  - url: 'https://github.com/patriksimek/vm2/security/advisories/GHSA-5h3f-q97h-ccvc'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100721'
  - url: >-
      https://github.com/patriksimek/vm2/commit/6ac3916da84e060c403e407b6b6318fcc66b0e72
  - url: >-
      https://github.com/patriksimek/vm2/commit/91034466bfb7f56b95fd48083ec6ca36d058f164
  - url: >-
      https://github.com/patriksimek/vm2/commit/ab4ee7d803e8c80155e9eb3672226bddbca4aa9c
  - url: >-
      https://www.vulncheck.com/advisories/vm2-before-3.12.2-authorization-bypass-via-custom-resolver
  - url: 'https://github.com/advisories/GHSA-c9wr-qm7p-p6vc'
tags:
  - ghsa
  - npm
ingestedAt: '2026-10-05T23:36:21.168Z'
---

## Overview

## Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-5h3f-q97h-ccvc. This link is maintained to preserve external references.

## Original Description
vm2 before 3.12.2 contains an authorization bypass in the NodeVM external-module resolver. When an embedder configures `require.external` with a custom resolver (and `context: 'host'`), `LegacyResolver.customResolve` in lib/resolver-compat.js records the resolved module directory in `this.externals` as `new RegExp('^' + escapeRegExp(resolvedPath))`, without requiring a path separator or end-of-string boundary. Untrusted guest code can therefore require the allowlisted module (e.g. `foo`) and then require the absolute path of a non-allowlisted sibling whose path merely shares the resolved prefix (e.g. `.../node_modules/foo2/index.js`); the sibling passes `isPathAllowedForModule` and is loaded through `hostRequire`, so its top-level code runs in the host process before the exports are wrapped with `vm.readonly`, resulting in a sandbox escape and arbitrary code execution in the host context.

## Affected packages

- `vm2 < 3.12.2`

## Remediation

Upgrade to a patched release:

- `vm2 3.12.2`