CVE-2026-92957: vm2 NodeVM builtin deny-list bypass via node:-prefixed specifiers

CVE-2026-92957 · Severity: critical · CVSS 9.9 · Published 2026-09-17

vm2 is a popular Node.js virtual machine library used to safely execute untrusted JavaScript code in an isolated sandbox. A flaw in how vm2 processes module denial policies allows attackers to bypass security restrictions and gain access to dangerous system APIs like child_process, which provides command execution capabilities. An attacker can escape the sandbox's intended restrictions by requiring modules using alternate naming conventions.

Technologies: vm2 (npm). Vendors: npm.

Quick answers

Is CVE-2026-92957 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-92957 being exploited in the wild.
How severe is CVE-2026-92957?
Critical severity, with a CVSS score of 9.9, published 17 September 2026.
Which products and versions are affected?
vm2 (npm) <= 3.11.6, SEMVER:introduced=0,fixed=3.11.7.
Is there a fix for CVE-2026-92957?
Yes. vm2 (npm): upgrade to 3.11.7 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-92957 attacked?
It is attacked over the network or with local access, in a software library.
Am I affected by CVE-2026-92957?
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 3.11.7 or later
    npm install vm2@3.11.7

Technical details

vm2's NodeVM normalizes node:-prefixed builtin module specifiers during require() resolution by stripping the prefix before loading, but does not apply the same normalization when evaluating negative (deny) entries in wildcard builtin policies. A deny rule like -node:child_process is matched by exact string comparison against canonical names (e.g., child_process), causing the comparison to fail. An attacker can require('child_process') or require('node:child_process') to bypass the intended denial and gain access to host process-spawning APIs such as execSync and spawn, effectively achieving command execution within the sandbox. The vulnerability affects NodeVM configurations using wildcard builtin policies with node:-prefixed negative entries. Fixed in vm2 3.11.7 by canonicalizing builtin names before allow/deny comparison.

Affected products

  • vm2 vm2 through 3.11.6

Identifiers

  • CVE-2026-92957
  • GHSA-8686-vhfx-7r3j

Timeline

  • 2026-08-24: disclosed
  • 2026-09-17: advisory
  • 2026-09-17: patched: Fixed in vm2 3.11.7

References

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