CVE-2026-34208

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.36, SandboxJS blocks direct assignment to global objects (for example Math.random = ...), but this protection can be bypassed through an exposed callable constructor path: this.constructor.call(target, attackerObject). Because this.constructor resolves to the internal SandboxGlobal function and Function.prototype.call is allowed, attacker code can write arbitrary properties into host global objects and persist those mutations across sandbox instances in the same process. This vulnerability is fixed in 0.8.36.

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 LOW

Scope CHANGED

References

Link	Resource
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-2gg9-6p7w-6cpj	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

09 Apr 2026, 18:07

Type	Values Removed	Values Added
First Time		Nyariv sandboxjs Nyariv
References	~~() https://github.com/nyariv/SandboxJS/security/advisories/GHSA-2gg9-6p7w-6cpj -~~	() https://github.com/nyariv/SandboxJS/security/advisories/GHSA-2gg9-6p7w-6cpj - Exploit, Vendor Advisory
CPE		cpe:2.3:a:nyariv:sandboxjs::::::node.js::*

06 Apr 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-06 16:16

Updated : 2026-04-09 18:07

NVD link : CVE-2026-34208

Mitre link : CVE-2026-34208

CVE.ORG link : CVE-2026-34208

JSON object : View

Products Affected

nyariv

sandboxjs

CWE

CWE-693

Protection Mechanism Failure

CWE-915

Improperly Controlled Modification of Dynamically-Determined Object Attributes

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