# CVE-2026-92951: vm2 module allowlist bypass via substring matching

Source: https://junglewise.ai/threats/cve-2026-92951-vm2-module-allowlist-bypass-via-substring-matching  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-17. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-92951 · Severity: critical · CVSS 9.9 · Published 2026-09-17

vm2 is a popular sandbox library used to safely execute untrusted JavaScript code in a Node.js environment while restricting access to system modules and external packages. The vulnerability allows attackers to bypass package restrictions by requesting a package name that contains an allowlisted substring (e.g., requesting "evil-left-pad" when only "left-pad" is allowed), leading to arbitrary code execution in the host context outside the sandbox.

Technologies: [vm2 (npm)](https://junglewise.ai/threats/technologies/vm2). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-92951 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-92951 being exploited in the wild.

**How severe is CVE-2026-92951?** Critical severity, with a CVSS score of 9.9, published 17 September 2026.

**Which products and versions are affected?** vm2 (npm) <= 3.11.6, SEMVER:introduced=0,fixed=3.11.7.

**Is there a fix for CVE-2026-92951?** Yes. vm2 (npm): upgrade to 3.11.7 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-92951 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-92951?** Check whether you run vm2 (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- vm2 (npm): upgrade to 3.11.7 or later

  ```sh
  npm install vm2@3.11.7
  ```


## Technical details

The vulnerability is an authorization bypass in NodeVM's external package allowlist mechanism. vm2 generates a regular expression from the allowlist but fails to anchor it to package-name boundaries, performing a substring match instead of an exact match. An attacker can request a colliding package name containing an allowlisted substring; if that colliding package exists in a path resolvable by the custom resolver, vm2 will load and execute it in the host context (when context: 'host' is configured), bypassing sandbox restrictions. This requires the colliding package to already be present in a resolvable path or for the application's dependency workflow to place it there. Patched in version 3.11.7.

## Affected products

- patriksimek vm2 before 3.11.7

## Identifiers

- CVE-2026-92951
- GHSA-c48m-32m9-vx93

## Timeline

- 2026-08-24: disclosed
- 2026-09-17: advisory
- 2026-09-17: patched: Fixed in version 3.11.7

## References

- [https://github.com/patriksimek/vm2/security/advisories/GHSA-c48m-32m9-vx93](https://github.com/patriksimek/vm2/security/advisories/GHSA-c48m-32m9-vx93)
- [https://www.vulncheck.com/advisories/vm2-before-3.11.7-module-allowlist-bypass-via-custom-resolver](https://www.vulncheck.com/advisories/vm2-before-3.11.7-module-allowlist-bypass-via-custom-resolver)

## Related threats

- [vm2 NodeVM path bypass in custom resolution](https://junglewise.ai/threats/duplicate-advisory-vm2-nodevm-custom-resolution-bypasses-external-path-5d3a7272)
- [vm2 NodeVM zlib buffer pool information disclosure](https://junglewise.ai/threats/duplicate-advisory-vm2-nodevm-zlib-buffers-expose-pooled-host-memory-6007c734)
- [vm2 host Promise rejection denial of service in construct trap](https://junglewise.ai/threats/duplicate-advisory-vm2-host-promise-rejection-from-an-exposed-f7aba6ba)
- [vm2 sandbox escape via Buffer backing-store ownership bypass](https://junglewise.ai/threats/cve-2026-100723-vm2-before-3-12-2-does-not-apply-its-buffer-backing-store)
- [vm2 unhandled Promise rejection in construct trap](https://junglewise.ai/threats/cve-2026-100722-vm2-before-3-12-2-does-not-apply-host-side-promise-rejection)