CVE-2026-43898
SandboxJS: Sandbox escape via Function.caller leakage of internal call op
CVSS Score
10.0
EPSS Score
0.0%
EPSS Percentile
0th
SandboxJS is a JavaScript sandboxing library. Prior to 0.9.6, sandbox-defined functions expose Function.caller, allowing sandboxed code to recover the internal LispType.Call runtime callback. That callback can then be invoked with attacker-controlled fake context and obj values to extract blocked host statics, recover the real host Function constructor, and execute arbitrary host JavaScript. This vulnerability is fixed in 0.9.6.
| CWE | CWE-94 |
| Vendor | nyariv |
| Product | sandboxjs |
| Published | May 28, 2026 |
| Last Updated | May 28, 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:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
nyariv / SandboxJS
< 0.9.6