VM2 Has Sandbox Breakout Through Inspect Function

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-24781: 1.19% estimated exploitation activity in the next 30 days; percentile 67.89 (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 suffers from a sandbox breakout vulnerability through the `inspect` function. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.

Details The node `inspect` method allows to log details of objects. To get to the details, the implementation unwraps proxies. The unwrapped values can be extracted using the `this.seen` of the `stylize` function. This allows to get access to the internal proxy handler of VM2 which contains the sandbox object. Since the access to the handler is itself wrapped by a VM2 proxy, accessing the sandbox object in the proxy handler will result in a wrapped sandbox object given into the sandbox. This allows to write a wrapped host object to the wrapped sandbox object and read the raw host object from the raw sandbox object bypassing the proxy bridge.

PoC ```js const obj = { subarray: Buffer.prototype.inspect, slice: Buffer.prototype.slice, hexSlice:()=>'', l:{proto:…

Published by the source

5 May 2026, 16:33 UTC

Last modified by the source

4 Nov 2026, 03:45 UTC

Source last checked

4 Nov 2026, 06:00 UTC

1. Revision 5 · amended · 4 Nov 2026

   Amended from osv record GHSA-v37h-5mfm-c47c

2. Revision 4 · amended · 4 Nov 2026

   Amended from ghsa record GHSA-v37h-5mfm-c47c

3. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-v37h-5mfm-c47c

4. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-v37h-5mfm-c47c

5. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-v37h-5mfm-c47c

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# Patch Next advisory brief: CVE-2026-24781

Advisory: VM2 Has Sandbox Breakout Through Inspect Function
IDs: CVE-2026-24781, GHSA-v37h-5mfm-c47c
Record: https://patchnext.com/advisories/cve-2026-24781 (revision 5, source checked 4 Nov 2026, 06:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: vm2 3.11.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm vm2: affected < 3.11.0; fixed in 3.11.0

## 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-v37h-5mfm-c47c (GitHub-reviewed advisory GHSA-v37h-5mfm-c47c lists affected ranges: npm vm2 >=0 <=3.10.3)
- Verified: https://osv.dev/vulnerability/GHSA-v37h-5mfm-c47c (OSV record GHSA-v37h-5mfm-c47c lists affected ranges: npm vm2 >=0 <3.11.0 (fixed))
- Verified: https://github.com/advisories/GHSA-v37h-5mfm-c47c (GitHub-reviewed advisory GHSA-v37h-5mfm-c47c lists affected ranges: npm vm2 >=0 <3.11.0)

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