# CVE-2026-92953: vm2 prototype pollution in TypedArray and ArrayBuffer

Source: https://junglewise.ai/threats/cve-2026-92953-vm2-prototype-pollution-in-typedarray-and-arraybuffer  
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-2026-92953 · Severity: critical · CVSS 10 · Published 2026-09-17

vm2 is a popular sandbox library that isolates untrusted JavaScript code. An attacker running code inside a default vm2 sandbox can bypass isolation protections and pollute the host application's TypedArray and ArrayBuffer prototypes, causing the host's typed-array objects to execute malicious code or observe attacker-controlled properties after the sandboxed code exits. This violates the core security boundary between sandbox and host.

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

## Quick answers

**Is CVE-2026-92953 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-92953 being exploited in the wild.

**How severe is CVE-2026-92953?** Critical severity, with a CVSS score of 10, published 17 September 2026.

**Which products and versions are affected?** vm2 (npm) >= 3.11.0, <= 3.11.7, SEMVER:introduced=3.11.0,fixed=3.11.8.

**Is there a fix for CVE-2026-92953?** Yes. vm2 (npm): upgrade to 3.11.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-92953 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-92953?** 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 3.11.8 or later

  ```sh
  npm install vm2@3.11.8
  ```


## Technical details

vm2 protects host object prototypes from sandbox mutation via a bridge mechanism that maintains a list of protected host intrinsics. However, the inventory omits TypedArray.prototype, ArrayBuffer.prototype, and related typed-array family prototypes. An attacker can use prototype-walking primitives (via Buffer.__proto__ lookups) to reach and mutate these unprotected host prototypes, causing Reflect.defineProperty() calls to forward into the real host objects rather than sandbox-local copies. No special privileges, NodeVM mode, or host-provided typed arrays are required. The fix is to extend the protected inventory to include all typed-array and binary-data intrinsics and apply the same mutation guards (set, defineProperty, deleteProperty, preventExtensions). Patches are available in version 3.11.8 and later.

## Affected products

- Patriksimek vm2 3.11.0 before 3.11.8

## Identifiers

- CVE-2026-92953
- GHSA-3vgf-8m4q-q4qr

## Timeline

- 2026-08-27: disclosed: Security advisory GHSA-3vgf-8m4q-q4qr published on GitHub
- 2026-09-17: advisory: CVE-2026-92953 published and indexed in NVD
- 2026: patched: Version 3.11.8 released with fix

## References

- [https://github.com/patriksimek/vm2/security/advisories/GHSA-3vgf-8m4q-q4qr](https://github.com/patriksimek/vm2/security/advisories/GHSA-3vgf-8m4q-q4qr)
- [https://www.vulncheck.com/advisories/vm2-3.11.0-through-3.11.7-prototype-pollution-via-typedarray](https://www.vulncheck.com/advisories/vm2-3.11.0-through-3.11.7-prototype-pollution-via-typedarray)

## 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)