Vulnerability · Published Mar 13, 2026 · Assigned by GitHub_M

CVE-2026-26954SandboxJS has a Sandbox Escape

Critical 10.0

In plain English

A critical-severity code injection in SandboxJS from nyariv. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)10.0Critical

Exploit odds (30 days)0.6%top 52.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.34, it is possible to obtain arrays containing Function, which allows escaping the sandbox. Given an array containing Function, and Object.fromEntries, it is possible to construct {[p]: Function} where p is any constructible property. This vulnerability is fixed in 0.8.34.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	@nyariv/sandboxjs	0.8.34	GHSA-6r9f-759j-hjgv

Affected products (as reported)

Vendor	Product	Versions
nyariv	SandboxJS	< 0.8.34

Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

References

https://github.com/nyariv/SandboxJS/security/advisories/GHSA-6r9f-759j-hjgv x_refsource_CONFIRM