SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, a sandbox escape is possible by shadowing hasOwnProperty on a sandbox object, which disables prototype whitelist enforcement in the property-access path. This permits direct access to __proto__ and other blocked prototype properties, enabling host Object.prototype pollution and persistent cross-sandbox impact. This vulnerability is fixed in 0.8.29.
History

Fri, 06 Feb 2026 21:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 06 Feb 2026 20:00:00 +0000

Type Values Removed Values Added
Description SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, a sandbox escape is possible by shadowing hasOwnProperty on a sandbox object, which disables prototype whitelist enforcement in the property-access path. This permits direct access to __proto__ and other blocked prototype properties, enabling host Object.prototype pollution and persistent cross-sandbox impact. This vulnerability is fixed in 0.8.29.
Title SandboxJS has a Sandbox Escape via Prototype Whitelist Bypass and Host Prototype Pollution
Weaknesses CWE-74
References
Metrics cvssV3_1

{'score': 10, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-02-06T20:17:19.095Z

Reserved: 2026-02-03T01:02:46.715Z

Link: CVE-2026-25586

cve-icon Vulnrichment

Updated: 2026-02-06T20:17:03.787Z

cve-icon NVD

Status : Received

Published: 2026-02-06T20:16:10.770

Modified: 2026-02-06T21:16:17.453

Link: CVE-2026-25586

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.