Junglewise Threat Intelligence

CVE-2026-24118: patriksimek vm2 sandbox breakout via descriptor-chain bypass

CVE-2026-24118 · Severity: critical · CVSS 9.8 · Published 2026-05-04

Technologies: Red Hat Self-service automation portal, Red Hat Self-service automation portal 2, Patriksimek Vm2, Red Hat Developer Hub. Vendors: Red Hat, npm.

Executive brief

vm2 is a popular software library used to run untrusted code in a secure, isolated environment (a sandbox). A critical flaw allows an attacker to break out of this isolation and run unauthorized commands directly on the underlying server. This could lead to a total system takeover, theft of sensitive data, or disruption of operations.

Technical details

A sandbox breakout vulnerability exists in vm2 due to improper handling of JavaScript proxies and host objects. Specifically, the vulnerability involves a descriptor-chain bypass of the `__lookupGetter__` and `Buffer.apply` constructor, as well as an 'Array species self-return' escape where V8's `ArraySpeciesCreate` reads `this.constructor[Symbol.species]` directly on raw objects, bypassing the bridge proxy. An attacker can provide malicious code to the sandbox that leaks host-side constructors or prototypes, leading to Remote Code Execution (RCE) on the host machine. The issue is addressed in version 3.11.0 by implementing a multi-layer defense in `lib/bridge.js` to neutralize host array constructors during function calls.

Affected products

  • patriksimek vm2 < 3.11.0
  • Red Hat Self-service automation portal 2
  • Red Hat Red Hat Developer Hub 1

Timeline

  • 2026-04-24: patched: Initial fix for Array species escape committed
  • 2026-05-01: advisory: GitHub Advisory GHSA-grj5-jjm8-h35p published
  • 2026-05-01: patched: Version 3.11.0 released
  • 2026-05-04: disclosed: NVD publication date

References

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