---
id: CVE-2026-100722
title: >-
  vm2 before 3.12.2 does not apply host-side Promise rejection handling in the
  sandbox-to-host construct trap
summary: >-
  vm2 before 3.12.2 does not apply host-side Promise rejection handling in the
  sandbox-to-host construct trap. In BaseHandler, the apply trap calls
  markHostPromiseHandled() on the returned value, but the adjacent construct
  path returns the…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H'
cwe:
  - CWE-248
vendor: patriksimek
product: vm2
affected:
  - vm2 < 3.12.2
published: '2026-09-27'
updated: '2026-09-27'
sourceUpdated: '2026-09-27T02:17:19.200'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100722'
references:
  - url: 'https://github.com/patriksimek/vm2/security/advisories/GHSA-2v2p-6j97-cjg9'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/vm2-before-3.12.2-host-process-termination-via-construct-trap
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-27T02:41:45.565Z'
---

## Overview

vm2 before 3.12.2 does not apply host-side Promise rejection handling in the sandbox-to-host construct trap. In BaseHandler, the apply trap calls markHostPromiseHandled() on the returned value, but the adjacent construct path returns the result of Reflect.construct without the same sanitization. If an embedder exposes a constructable host function whose constructor returns a native rejected Promise, an untrusted script executed via VM.run can invoke it with `new` and ignore the result; the rejected host Promise crosses the bridge unhandled and, under Node's strict unhandled-rejection policy, is promoted to an uncaught exception that terminates the host process.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.