CVE-2026-21636
published 2026-01-20CVE-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…
PriorityP266critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
EPSS
0.83%
54.6th percentile
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.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | nodejs | — | — |
| nodejs | node | 25.2.1 – 25.2.1 | — |
| nodejs | node.js | >= 25.0.0 < 25.3.0 | 25.3.0 |
Detection & IOCsextracted from sources · hover to see the quote
- →Look for Node.js processes launched with `--permission` flag but without `--allow-net`, where attacker-controlled socketPath options or URLs are passed to net, tls, or undici/fetch — this is the bypass vector for UDS connections ↗
- →Monitor Node.js v25 processes using the permission model (`--permission`) for unexpected Unix Domain Socket connections to privileged local services ↗
- ·Vulnerability is specific to Node.js v25 only; versions v20, v22, and v24 are confirmed not affected ↗
- ·The exploited feature (`--allow-net` / network permissions) is still experimental at the time of disclosure, meaning the permission model's network enforcement is not production-stable ↗
- ·Red Hat packages nodejs20, nodejs22, nodejs24 across RHEL 8, 9, and 10 are all confirmed not affected ↗
- ·No mitigation meeting Red Hat Product Security criteria is currently available ↗
CVSS provenance
nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvdv3.05.8MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
osv10.0CRITICAL
vendor_debian10.0LOW
vendor_redhat10.0CRITICAL
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Red Hat
nodejs: Nodejs network segmentation bypass
vendor_redhat·2026-01-20·CVSS 10.0
CVE-2026-21636 [CRITICAL] CWE-281 nodejs: Nodejs network segmentation bypass
nodejs: Nodejs network segmentation bypass
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.
A flaw in Node.js's permission model allows Unix Domain Socket (
Debian
CVE-2026-21636: nodejs - A flaw in Node.js's permission model allows Unix Domain Socket (UDS) connections...
vendor_debian·2026·CVSS 10.0
CVE-2026-21636 [CRITICAL] CVE-2026-21636: nodejs - A flaw in Node.js's permission model allows Unix Domain Socket (UDS) connections...
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.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved
sid: resolved
trixie: resolved
OSV
CVE-2026-21636: A flaw in Node
osv·2026-01-20·CVSS 10.0
CVE-2026-21636 [CRITICAL] CVE-2026-21636: A flaw in Node
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.
GHSA
GHSA-7xhv-hcmf-4rfv: A flaw in Node
ghsa_unreviewed·2026-01-20
CVE-2026-21636 [MEDIUM] CWE-284 GHSA-7xhv-hcmf-4rfv: A flaw in Node
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.
No detection rules found.
No public exploits indexed.
2026-01-20
Published