CVE-2026-34217

SandboxJS has a Sandbox Escape via Prop Object Leak in New Handler

Published Apr 6, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed
Description
SandboxJS is a JavaScript sandboxing library. Prior to 0.8.36, a scope modification vulnerability exists in @nyariv/sandboxjs. The vulnerability allows untrusted sandboxed code to leak internal interpreter objects through the new operator, exposing sandbox scope objects in the scope hierarchy to untrusted code; an unexpected and undesired exploit. While this could allow modifying scopes inside the sandbox, code evaluation remains sandboxed and prototypes remain protected throughout the execution. This vulnerability is fixed in 0.8.36.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-hg73-4w7g-q96w SandboxJS: Sandbox Escape via Prop Object Leak in New Handler
History
Type Values Removed Values Added
CPEs cpe:2.3:a:nyariv:sandboxjs:*:*:*:*:*:node.js:*:*
Metrics cvssV3_1

{'score': 7.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N'}

Type Values Removed Values Added
First Time appeared Nyariv
Nyariv sandboxjs
Vendors & Products Nyariv
Nyariv sandboxjs
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description SandboxJS is a JavaScript sandboxing library. Prior to 0.8.36, a scope modification vulnerability exists in @nyariv/sandboxjs. The vulnerability allows untrusted sandboxed code to leak internal interpreter objects through the new operator, exposing sandbox scope objects in the scope hierarchy to untrusted code; an unexpected and undesired exploit. While this could allow modifying scopes inside the sandbox, code evaluation remains sandboxed and prototypes remain protected throughout the execution. This vulnerability is fixed in 0.8.36.
Title SandboxJS has a Sandbox Escape via Prop Object Leak in New Handler
Weaknesses CWE-668
References
Metrics cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Apr 6, 2026, 3:40 PM
Reserved
Mar 26, 2026, 3:57 PM
Status
Analyzed
Published
Apr 6, 2026, 4:16 PM
Modified
Oct 26, 2026, 10:10 PM