CVE-2026-8162
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 · unedited[email protected] and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a Content-Disposition header whose filename* parameter contains a malformed percent-encoding, the parser invokes decodeURI on the value without try/catch. The resulting URIError propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to [email protected] or higher.
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 confidenceThe multiparty library versions 4.2.3 and below contain a denial of service vulnerability in its multipart/form-data parser. When processing Content-Disposition headers with malformed percent-encoded filename* parameters, the code calls decodeURI() without try/catch exception handling. This causes an uncaught URIError that crashes the Node.js process.
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< 4.3.0CVSS 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.
-
Check multiparty library versionRun 'npm list multiparty' in your project directory, or view the version listed in your package.json file under dependencies or devDependenciesAffected if The installed version is 4.2.3 or below (any version less than 4.3.0)
-
Confirm multipart form parsing is in useSearch your codebase for instances of 'form.parse' from multiparty, or look for code that requires multiparty and invokes the parser on incoming requestsAffected if Your application uses multiparty to parse multipart/form-data requests, typically for handling file uploads
-
Check for file upload handling with Content-DispositionExamine the code that processes parsed multipart files, specifically looking for access to the 'filename' or 'headers' properties from the parsed parts, which contain Content-Disposition dataAffected if Your multipart parsing code accesses filename information or Content-Disposition headers from uploaded files
You are affected if you have multiparty version less than 4.3.0 installed AND your application uses multiparty to parse multipart/form-data requests containing files with Content-Disposition headers that could include filename* parameters.
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.
dbcve · scoped4.3.0
Upgrade multiparty to version 4.3.0 or higher, which implements proper exception handling around the decodeURI call.
[email protected] or higher
- 1. Update the multiparty dependency in package.json to version 4.3.0 or higher (e.g., "multiparty": ">=4.3.0")
- 2. Run npm install or yarn install to download and install the fixed package version
- 3. Restart the application to ensure the updated package is loaded
- 4. Verify the fix by testing multipart form uploads with malformed percent-encoded filename* parameters in the Content-Disposition header
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 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 $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-8162 — 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-2026-8162 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