CVE-2021-34865
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 · uneditedThis vulnerability allows network-adjacent attackers to bypass authentication on affected installations of multiple NETGEAR routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the mini_httpd service, which listens on TCP port 80 by default. The issue results from incorrect string matching logic when accessing protected pages. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root. Was ZDI-CAN-13313.
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 confidenceThis vulnerability in NETGEAR router mini_httpd service (TCP port 80) allows unauthenticated network-adjacent attackers to bypass authentication through incorrect string matching logic when accessing protected pages. The flaw enables privilege escalation to root context and arbitrary code execution.
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< 1.2.0.88< 1.2.0.88< 1.2.0.88< 1.0.1.80< 1.1.0.110< 1.1.0.110< 1.1.0.84< 1.1.0.84CVSS 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
- Adjacent
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.
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Identify the NETGEAR router modelLog into the router admin interface and check the device info page, or look at the physical device label, or use network discovery to identify the model from MAC vendor prefix or HTTP headerAffected if The model is one of: Ac2100, Ac2400, Ac2600, D7000v1, R6220, R6230, R6260, or R6330
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Determine the installed firmware versionIn the router web interface, go to Administration > Firmware Update or Advanced > Administration > Router Update to view the current firmware version; alternatively, check the download file name if you have local firmwareAffected if The firmware version is below 1.2.0.88 (for Ac2100/Ac2400/Ac2600), below 1.0.1.80 (for D7000v1), below 1.1.0.110 (for R6220/R6230), or below 1.1.0.84 (for R6260/R6330)
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Check if mini_httpd service is accessible on TCP port 80From a network-adjacent host, run `nmap -p 80 <router-ip>` or `curl -I http://<router-ip>` to verify the HTTP service is reachableAffected if TCP port 80 responds with HTTP and returns a NETGEAR login page or admin interface
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Verify web management interface is exposed to network-adjacent attackersCheck router settings under Advanced > Remote Management (or similar) to see if "Web Management" or "HTTP" access is enabled from WAN or local network; confirm the router is directly accessible on port 80 without VPNAffected if The router HTTP service is reachable from an untrusted network segment or the internet
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Test authentication bypass conditionSend a crafted request to protected admin endpoints (such as `/BRS_netgear_success.html` or similar) to confirm the vulnerability exists; use a tool like Burp or curl to probe the authentication mechanismAffected if Requests to protected pages return admin content or bypass authentication without valid credentials
The environment is affected if the router model and firmware version fall within the affected ranges AND the mini_httpd service on TCP port 80 is accessible to network-adjacent attackers.
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 · scoped1.0.1.801.1.0.841.1.0.110
Apply available NETGEAR firmware updates for affected router models; if no patch exists, disable remote web management or place routers behind a firewall to limit exposure.
Firmware 1.2.0.88 (Ac2100/Ac2400/Ac2600), 1.0.1.80 (D7000v1), 1.1.0.110 (R6220/R6230), or 1.1.0.84 (R6260/R6330)
- 1. Identify your NETGEAR router model from the affected list (Ac2100, Ac2400, Ac2600, D7000v1, R6220, R6230, R6260, or R6330)
- 2. Visit the NETGEAR support website (kb.netgear.com) and locate the firmware download page for your specific router model
- 3. Download the firmware version 1.2.0.88 (for Ac2100/Ac2400/Ac2600), 1.0.1.80 (for D7000v1), 1.1.0.110 (for R6220/R6230), or 1.1.0.84 (for R6260/R6330)
- 4. Access your router's web management interface by entering the router's IP address in a web browser
- 5. Navigate to the Administration or Advanced settings section, then locate the Firmware Update option
- 6. Upload the downloaded firmware file and wait for the update process to complete
- 7. After the router restarts, verify the firmware version has been updated to the fixed release
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2021-34865 — 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-2021-34865 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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