Node.jsApplication
CVE-2026-21711
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA flaw in Node.js Permission Model network enforcement leaves Unix Domain Socket (UDS) server operations without the required permission checks, while all comparable network paths correctly enforce them. As a result, code running under `--permission` without `--allow-net` can create and expose local IPC endpoints, allowing communication with other processes on the same host outside of the intended network restriction boundary. This vulnerability affects Node.js **25.x** processes using the Permission Model where `--allow-net` is intentionally omitted to restrict network access. Note that `--allow-net` is currently an experimental feature.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceNode.js 25.x Permission Model incorrectly omits permission checks for Unix Domain Socket (UDS) server creation, allowing code running with --permission but without --allow-net to still create local IPC endpoints and communicate with other processes on the same host, bypassing the intended network restriction boundary.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Node.jsApplication
< 20.0.0>= 25.0.0, <= 25.8.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Node.js versionRun `node --version` to determine the installed Node.js versionAffected if Version is 25.x (any subversion)
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Check if Permission Model is enabledReview application startup scripts, process arguments, or environment for the `--permission` flag being passed to the Node.js processAffected if The `--permission` flag is present in the Node.js execution command
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Verify network permission configurationReview the permission flags passed to Node.js. Look specifically for whether `--allow-net` is absent or explicitly set to restrict network accessAffected if `--permission` is used but `--allow-net` is NOT granted (the intended restriction that can be bypassed)
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Inspect for Unix Domain Socket usageSearch application code for `net.createServer()` or `server.listen()` calls that use a file path string as the address (e.g., `server.listen('/tmp/socket.sock')`), or for `path` module usage creating socket filesAffected if The application creates Unix Domain Socket servers while using restricted permissions without explicit UDS allowance
You are affected if running Node.js 25.x with the experimental Permission Model enabled (`--permission`) and network access is restricted (no `--allow-net`), while the application creates or could create Unix Domain Socket endpoints.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor data20.0.0
Avoid using the experimental Node.js Permission Model for security-critical deployments until the vulnerability is patched; alternatively, monitor for Node.js security releases addressing this UDS permission bypass.
Fix this in Node.js
Scoped from the published advisory
- Consultation2.0 h
- Testing1.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,200.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21711 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-21711 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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