Node.jsApplication
CVE-2020-8251
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 · uneditedNode.js < 14.11.0 is vulnerable to HTTP denial of service (DoS) attacks based on delayed requests submission which can make the server unable to accept new connections.
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 versions prior to 14.11.0 contain a vulnerability in the HTTP server implementation where delayed request submission can cause connection exhaustion, preventing the server from accepting new connections. This is a denial-of-service vulnerability affecting the HTTP subsystem.
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
>= 14.0.0, < 14.11.0
FedoraOperating system
= 33CVSS 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
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
-
Determine installed Node.js versionRun 'node --version' or 'node -v' in the terminalAffected if The version shown is 14.0.0 through 14.10.x (any version >= 14.0.0 and < 14.11.0)
-
Check if HTTP server module is in useSearch codebase for require('http'), http.createServer(), or use of frameworks that wrap Node.js HTTP (such as Express with default HTTP server)Affected if The application creates HTTP servers without additional connection limiting middleware
-
Identify if server accepts external connectionsReview server binding configuration - check for listen() calls binding to 0.0.0.0 or external interfaces versus localhost onlyAffected if Server listens on external network interfaces (0.0.0.0 or any IP other than 127.0.0.1)
-
Verify if delayed or slow client connections are possibleCheck if the HTTP server is exposed to untrusted clients or if there are proxy/gateway configurations that could accept delayed request submissionsAffected if Server accepts connections from untrusted or public network sources
A user is affected if their Node.js version is 14.0.0 through 14.10.x and they run an HTTP server accepting connections from untrusted clients without additional connection throttling.
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 data14.11.0
Upgrade Node.js to version 14.11.0 or later to receive the security patch. In production environments, test the upgrade for application compatibility before deploying.
Fix this in Node.js
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 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 $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-8251 — 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-2020-8251 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data