CVE-2026-25586

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.

CVSS v3 10.0 CRITICAL

10.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

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/67cb186c41c78c51464f70405504e8ef0a6e43c3	Patch
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-jjpw-65fv-8g48	Exploit Vendor Advisory
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-jjpw-65fv-8g48	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-02-06 20:16

Updated : 2026-02-18 14:32

NVD link : CVE-2026-25586

Mitre link : CVE-2026-25586

CVE.ORG link : CVE-2026-25586

JSON object : View

Products Affected

nyariv

sandboxjs

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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