CVE-2026-25881

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.31, a sandbox escape vulnerability allows sandboxed code to mutate host built-in prototypes by laundering the isGlobal protection flag through array literal intermediaries. When a global prototype reference (e.g., Map.prototype, Set.prototype) is placed into an array and retrieved, the isGlobal taint is stripped, permitting direct prototype mutation from within the sandbox. This results in persistent host-side prototype pollution and may enable RCE in applications that use polluted properties in sensitive sinks (example gadget: execSync(obj.cmd)). This vulnerability is fixed in 0.8.31.

CVSS v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.2 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/nyariv/SandboxJS/commit/f369f8db26649f212a6a9a2e7a1624cb2f705b53	Patch
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-ww7g-4gwx-m7wj	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nyariv:sandboxjs:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-02-09 22:16

Updated : 2026-02-18 18:07

NVD link : CVE-2026-25881

Mitre link : CVE-2026-25881

CVE.ORG link : CVE-2026-25881

JSON object : View

Products Affected

nyariv

sandboxjs

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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