CVE-2026-25587
Prototype Pollution in SandboxJS Map.prototype Enables Sandbox Escape
Publication date: 2026-02-06
Last updated on: 2026-02-18
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nyariv | sandboxjs | to 0.8.29 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-94 | The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. |
Attack-Flow Graph
AI Powered Q&A
How can this vulnerability impact me? :
Exploiting this vulnerability allows an attacker to escape the sandbox, which is intended to isolate and restrict code execution. This can lead to complete compromise of the system where the sandbox is used, including full control over confidentiality, integrity, and availability of the affected environment.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, upgrade the SandboxJS library to version 0.8.29 or later where the issue is fixed.
Can you explain this vulnerability to me?
This vulnerability exists in SandboxJS, a JavaScript sandboxing library, in versions prior to 0.8.29. The issue arises because the Map object is included in SAFE_PROTOTYPES, allowing its prototype to be accessed via Map.prototype. An attacker can exploit this by overwriting the Map.prototype.has method, which enables them to escape the sandbox environment.