CVE-2026-21636 (GCVE-0-2026-21636)

Vulnerability from cvelistv5 – Published: 2026-01-20 20:41 – Updated: 2026-01-21 18:52
VLAI?
Summary
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.
Severity ?
5.8 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
CWE
  • CWE-284 - Improper Access Control
Assigner
References
Impacted products
Vendor Product Version
nodejs node Affected: 25.2.1 , ≤ 25.2.1 (semver)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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