CVE-2021-34982
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 · uneditedNETGEAR Multiple Routers httpd Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of multiple NETGEAR routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the httpd service, which listens on TCP port 80 by default. When parsing the strings file, the process does not properly validate the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. . Was ZDI-CAN-13709.
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 confidenceStack-based buffer overflow in the httpd service on NETGEAR routers when parsing the strings file without validating data length before copying to a fixed-size stack buffer. This allows unauthenticated network-adjacent attackers to execute arbitrary code as the root user.
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< 1.0.0.62< 1.0.0.94< 1.0.0.94< 1.0.0.66< 1.0.0.46< 1.0.1.106< 1.0.1.76< 1.1.6.122CVSS 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:3.0/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 router modelCheck the device label or web interface for the exact Netgear model number (e.g., Ex3700, Mr60, Dc112a)Affected if Model is one of: Dc112a, Ex3700, Ex3800, Ex6120, Ex6130, Ex7000, Ex7500, or Mr60
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Check installed firmware versionAccess router web interface (typically at 192.168.1.1) and navigate to Administration > Firmware Update, or check the device label. Compare against the affected version threshold for your specific modelAffected if Firmware version is below: Dc112a < 1.0.0.62, Ex3700/Ex3800 < 1.0.0.94, Ex6120 < 1.0.0.66, Ex6130 < 1.0.0.46, Ex7000 < 1.0.1.106, Ex7500 < 1.0.1.76, Mr60 < 1.1.6.122
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Confirm httpd service is runningAccess router via telnet or SSH (if enabled) and run: ps | grep httpd or check that the web server on port 80/443 is respondingAffected if httpd process is active and the router web interface is accessible on the network
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Verify remote management exposureIn router web interface, check Advanced > Remote Management or similar settings. Determine if httpd is accessible from WAN (internet) interfaces rather than only LANAffected if Remote management is enabled or httpd is exposed to WAN IP addresses
You are affected if your router model matches one of the listed products AND your firmware version is below the specified threshold AND the httpd service is network-accessible.
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 · scoped1.0.0.461.0.0.621.0.0.66
Apply NETGEAR firmware updates when available; until then, restrict network access to the router's HTTP service (port 80) and disable remote management from untrusted networks.
Model-specific firmware: Dc112a >= 1.0.0.62 | Ex3700/Ex3800 >= 1.0.0.94 | Ex6120 >= 1.0.0.66 | Ex6130 >= 1.0.0.46 | Ex7000 >= 1.0.1.106 | Ex7500 >= 1.0.1.76 | Mr60 >= 1.1.6.122
- 1. Identify the NETGEAR router model from the affected list: Dc112a, Ex3700, Ex3800, Ex6120, Ex6130, Ex7000, Ex7500, or Mr60
- 2. Access the router's web management interface by navigating to router's IP address (typically 192.168.1.1)
- 3. Check the current firmware version under Administration > Firmware Update or similar menu
- 4. Download the appropriate firmware update from the official NETGEAR support site (support.netgear.com) for your specific model
- 5. In the router's web interface, navigate to the firmware update section and upload the downloaded firmware file
- 6. Wait for the firmware upload and installation to complete - do not power off the router during this process
- 7. After reboot, verify the firmware version has been updated to the fixed version or higher
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2021-34982 — 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-2021-34982 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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