CVE-2026-21636

Date: January 20, 2026

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.