CVE-2026-34208
SandboxJS: Sandbox integrity escape
CVSS Score
10.0
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-693 CWE-915 |
| Vendor | nyariv |
| Product | sandboxjs |
| Published | Apr 6, 2026 |
| Last Updated | Apr 6, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
Low
Affected Versions
nyariv / SandboxJS
< 0.8.36