CVE-2026-34208

critical · 10

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

0.6%

EPSS (exploit prob.)

45th

EPSS percentile

2026-04-06

Published

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

Weaknesses

CWE-693CWE-915

Affected products

Vendor	Product	Affected versions
nyariv	sandboxjs	< 0.8.36

Check a specific version with /api/v1/cve/match.

References

https://github.com/nyariv/SandboxJS/security/advisories/GHSA-2gg9-6p7w-6cpj

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-34208