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Fencer Intel
critical 9.9

CVE-2026-43999 json

vm2: NodeVM builtin allowlist bypass via `module` builtin's `Module._load` allows sandbox escape

published 6mo ago modified 14d ago also EUVD-2026-30069 , GHSA-947f-4v7f-x2v8

cvss
9.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits
0
none known

Summary

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.0, NodeVM's builtin allowlist can be bypassed when the module builtin is allowed (including via the '*' wildcard). The module builtin exposes Node's Module._load(), which loads any module by name directly in the host context, completely bypassing vm2's builtin restriction. This allows sandboxed code to load excluded builtins like child_process and achieve remote code execution. This vulnerability is fixed in 3.11.0.

Patch / fix

  • npm vm2 3.11.0
  • Red Hat Red Hat Ansible Automation Platform 2.1 1785854226

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-43999 updated cvss 9.9

vm2: vm2: Remote code execution via NodeVM builtin allowlist bypass

  • Red Hat Ansible Automation Platform 2.1 ansible-automation-platform/automation-portal 1785854226
    fixed: vendor fix RHSA-2026:50850
  • Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
5mo ago

Exploit prediction

0.97% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/patriksimek/vm2/security/advisories/GHSA-947f-4v7f-x2v8 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CISA ADP 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
GitHub 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
npm vm2
>=3.10.5, <3.11.0
3.11.0

Affected products

  • patriksimek vm2
  • Red Hat Red Hat Ansible Automation Platform 2.1
  • Red Hat Red Hat Developer Hub

Classification

Weakness
  • CWE-863 Incorrect Authorization
  • CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.