CVE-2026-21636

Published Jan 20, 2026

Last updated a month ago

Overview

Description
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.
Source
support@hackerone.com
NVD status
Analyzed
Products
node.js

Risk scores

CVSS 3.1

Type
Primary
Base score
10
Impact score
6
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Severity
CRITICAL

CVSS 3.0

Type
Secondary
Base score
5.8
Impact score
1.4
Exploitability score
3.9
Vector string
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Severity
MEDIUM

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-284

Social media

Hype score
Not currently trending

Configurations

References

Sources include official advisories and independent security research.