CVE-2018-21202
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 · uneditedCertain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects D7800 before 1.0.1.30, R6100 before 1.0.1.20, R7500 before 1.0.0.118, R7500v2 before 1.0.3.24, R7800 before 1.0.2.40, R9000 before 1.0.2.52, WNDR3700v4 before 1.0.2.96, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.54, and WNDR4500v3 before 1.0.0.54.
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 confidenceMultiple NETGEAR router models contain a stack-based buffer overflow vulnerability that can be exploited by an unauthenticated attacker via the network. The vulnerability affects the web management interface and allows remote code execution or denial of service. Affected devices include D7800, R6100, R7500, R7500v2, R7800, R9000, WNDR3700v4, WNDR4300, WNDR4300v2, and WNDR4500v3 running firmware versions prior to the specified patched releases.
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< 1.0.1.30< 1.0.1.20< 1.0.3.24< 1.0.2.40< 1.0.2.52< 1.0.2.96< 1.0.2.98< 1.0.0.54< 1.0.0.54CVSS 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.
-
Identify router modelLog into the router web management interface and locate the model number typically displayed on the dashboard or in the Device Info page. Alternatively, check the physical device label.Affected if Model is D7800, R6100, R7500, R7500v2, R7800, R9000, WNDR3700v4, WNDR4300, WNDR4300v2, or WNDR4500v3
-
Check firmware versionIn the router web management interface, navigate to Administration > Firmware Update or Device Info section. Record the exact firmware version displayed.Affected if Firmware version is below: D7800 < 1.0.1.30, R6100 < 1.0.1.20, R7500 < 1.0.3.24, R7800 < 1.0.2.40, R9000 < 1.0.2.52, WNDR3700v4 < 1.0.2.96, WNDR4300 < 1.0.2.98 (or < 1.0.0.54 for v2), WNDR4500v3 < 1.0.0.54
-
Confirm web management interface is enabledIn the router web management interface, go to Administration > Remote Management or similar. Check if remote web management access is enabled.Affected if Remote web management is enabled and the router is accessible from untrusted networks
If the device model is among the affected models AND the installed firmware version is below the specified thresholds AND remote web management is exposed, the device is vulnerable to CVE-2018-21202.
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 data1.0.0.541.0.1.201.0.1.30
Update affected NETGEAR devices to firmware versions at or above: D7800 1.0.1.30, R6100 1.0.1.20, R7500 1.0.0.118, R7500v2 1.0.3.24, R7800 1.0.2.40, R9000 1.0.2.52, WNDR3700v4 1.0.2.96, WNDR4300 1.0.2.98, WNDR4300v2 1.0.0.54, WNDR4500v3 1.0.0.54. If devices cannot be patched, disable remote web management and segment them from untrusted networks.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 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 $3,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-21202 — 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-2018-21202 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