CVE-2026-25520 CRITICAL

CVE-2026-25520: SandboxJS has a Sandbox Escape

Vendor Nyariv
Product SandboxJS
Weakness CWE-74
Published February 6, 2026
Last update February 6, 2026
View on NVD All CVEs

CVSS base score

10.0/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, The return values of functions aren't wrapped. Object.values/Object.entries can be used to get an Array containing the host's Function constructor, by using Array.prototype.at you can obtain the hosts Function constructor, which can be used to execute arbitrary code outside of the sandbox. This vulnerability is fixed in 0.8.29.

Key dates

02Disclosure timeline

February 6, 2026 CVE published
February 6, 2026 Record updated