# CVE-2026-44005: patriksimek vm2 sandbox escape via host prototype mutation

Source: https://junglewise.ai/threats/cve-2026-44005-patriksimek-vm2-sandbox-escape-via-host-prototype-mutation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-13. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-44005 · Severity: critical · CVSS 10 · Published 2026-05-13

vm2 is a popular software library used to run untrusted code in a secure, isolated 'sandbox' environment. A critical flaw allows an attacker to break out of this isolation and modify the core settings of the underlying server. This can lead to full control over the host system, potentially resulting in data theft, service disruption, or unauthorized access to the broader corporate network.

Technologies: [vm2 (npm)](https://junglewise.ai/threats/technologies/vm2), [Red Hat Self-service automation portal](https://junglewise.ai/threats/technologies/self-service-automation-portal). Vendors: [npm](https://junglewise.ai/threats/vendors/npm), [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-44005 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-44005 being exploited in the wild.

**How severe is CVE-2026-44005?** Critical severity, with a CVSS score of 10, published 13 May 2026.

**Which products and versions are affected?** vm2 (npm) >= 3.9.6, <= 3.10.5, SEMVER:introduced=3.9.6,fixed=3.11.0; Red Hat Self-service automation portal 2.

**Is there a fix for CVE-2026-44005?** Yes. vm2 (npm): upgrade to 3.11.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-44005 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-44005?** Check whether you run vm2 (npm) or Red Hat Self-service automation portal 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 3.11.0 or later

  ```sh
  npm install vm2@3.11.0
  ```


## Technical details

A sandbox escape vulnerability exists in vm2 versions 3.9.6 through 3.10.5 due to improper isolation in the bridge component. The bridge exposes mutable proxies for host-realm intrinsic prototypes and incorrectly forwards sandbox writes to the underlying host objects using otherReflectSet() and otherReflectDefineProperty(). An attacker can use a prototype-walking primitive to reach and mutate the host's Object.prototype, Array.prototype, or Function.prototype. This prototype pollution allows for arbitrary code execution on the host machine. The issue is fixed in version 3.11.0.

## Affected products

- patriksimek vm2 3.9.6-3.10.5
- Red Hat Self-service automation portal 2 2

## Identifiers

- CVE-2026-44005
- GHSA-vwrp-x96c-mhwq

## Timeline

- 2026-05-01: advisory: Original GitHub advisory published by patriksimek
- 2026-05-13: disclosed: CVE-2026-44005 published to NVD
- 2026-05-13: patched: Fix released in version 3.11.0

## References

- [https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq](https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq)
- [https://access.redhat.com/security/cve/CVE-2026-44005](https://access.redhat.com/security/cve/CVE-2026-44005)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2477205](https://bugzilla.redhat.com/show_bug.cgi?id=2477205)
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44005.json](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44005.json)

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- [vm2 NodeVM zlib buffer pool information disclosure](https://junglewise.ai/threats/duplicate-advisory-vm2-nodevm-zlib-buffers-expose-pooled-host-memory-6007c734)
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