CVE-2024-46571
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 · uneditedDraytek Vigor 3910 v4.3.2.6 was discovered to contain a buffer overflow in the sPPPSrvNm parameter at fwuser.cgi. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted input.
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 confidenceA buffer overflow vulnerability exists in Draytek Vigor 3910 router firmware v4.3.2.6 within the fwuser.cgi web interface. The sPPPSrvNm parameter (PPP server name field) fails to properly validate input length, allowing an attacker to send oversized crafted data that overflows the buffer and causes the device to crash, resulting in denial of service.
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= 4.3.2.6CVSS 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.
-
Confirm device model is Draytek Vigor 3910Access the router web interface or use SNMP/CLI to query the device model. Look for 'Vigor3910' in the system information page or banner.Affected if Device model is not Vigor 3910, then the CVE does not apply.
-
Check installed firmware versionNavigate to the router web interface System Maintenance > Firmware Upgrade page, or use the CLI command 'sys mnginfo' to display firmware version. Compare the version number to 4.3.2.6.Affected if Firmware version is exactly 4.3.2.6, then the device is affected.
-
Verify fwuser.cgi is accessibleAttempt to access the web interface endpoint '/cgi-bin/fwuser.cgi' or check if the PPP server configuration page is reachable from the web UI under PPP settings.Affected if The web interface and fwuser.cgi are exposed and reachable on the network.
-
Check if PPP server name configuration is exposedIn the router web interface, navigate to PPP configuration or WAN settings where the PPP server name (sPPPSrvNm) parameter can be configured or viewed.Affected if The PPP server name field is configurable or visible through the web interface.
The device is affected only if it is a Draytek Vigor 3910 running firmware version 4.3.2.6 with the fwuser.cgi web interface accessible on the network.
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 dataApply vendor firmware patches when available; in the interim, restrict network access to the administrative web interface (fwuser.cgi) to prevent unauthenticated attackers from exploiting this flaw.
- Consultation4.0 h
- Implementation6.0 h
- Testing8.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,504.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2024-46571 — 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-2024-46571 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