Vulnerability · Published Feb 6, 2026 · Assigned by GitHub_M
CVE-2026-25587SandboxJS 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 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)10.0Critical
Exploit odds (30 days)0.7%top 46.6% 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 0.8.29, as Map is in SAFE_PROTOYPES, it's prototype can be obtained via Map.prototype. By overwriting Map.prototype.has the sandbox can be escaped. This vulnerability is fixed in 0.8.29.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @nyariv/sandboxjs | 0.8.29 | GHSA-66h4-qj4x-38xp |
Affected products (as reported)
Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H