CVE-2026-34208CRITICAL 10.0EPSS p42.2%
CVE-2026-34208CVE-2026-34208
Description
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.
Scoring
| CVSS 3.1 | 10.0 (CRITICAL) |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| EPSS | 0.56% probability of exploitation · percentile 42.2% · 2026-06-19T12:03:05Z |
| Published | 2026-04-06 |
| Last modified | 2026-04-09 |
Underlying weaknesses· 2
References
2
| Type | Target | Confidence | Tier |
|---|---|---|---|
| Weakness | Protection Mechanism Failurecwe-693 | 0% | live |
| Weakness | Improperly Controlled Modification of Dynamically-Determined Object Attributescwe-915 | 0% | live |
Related by meaning· 6
Nearest entities by semantic similarity across the cs-graph corpus.