CVE-2026-21636

A flaw in Node.js's permission model allows Unix Domain Socket (UDS) connections to bypass network restrictions when `--permission` is enabled. Even without `--allow-net`, attacker-controlled inputs (such as URLs or socketPath options) can connect to arbitrary local sockets via net, tls, or undici/fetch. This breaks the intended security boundary of the permission model and enables access to privileged local services, potentially leading to privilege escalation, data exposure, or local code execution. * The issue affects users of the Node.js permission model on version v25. In the moment of this vulnerability, network permissions (`--allow-net`) are still in the experimental phase.

CVSS v3 10.0 CRITICAL

10.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://nodejs.org/en/blog/vulnerability/december-2025-security-releases	Vendor Advisory Release Notes

Configurations

Configuration 1 (hide)

cpe:2.3:a:nodejs:node.js:*:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-01-20 21:16

Updated : 2026-01-30 20:20

NVD link : CVE-2026-21636

Mitre link : CVE-2026-21636

CVE.ORG link : CVE-2026-21636

JSON object : View

Products Affected

nodejs

node.js

CWE

CWE-284

Improper Access Control

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