CVE-2018-21208
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 command injection by an unauthenticated attacker. This affects D6100 before 1.0.0.57, R6100 before 1.0.1.20, R7500v2 before 1.0.3.24, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.
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 confidenceUnauthenticated command injection vulnerability in specific NETGEAR router firmware versions (D6100, R6100, R7500v2, WNDR4300v2, WNDR4500v3). An unauthenticated network attacker can inject arbitrary OS commands through the web interface, potentially achieving full device compromise.
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< 1.0.0.57< 1.0.1.20< 1.0.3.24< 1.0.0.50< 1.0.0.50CVSS 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 model name, typically displayed on the main status page or on a label on the device itselfAffected if The device is NOT one of: D6100, R6100, R7500v2, WNDR4300v2, or WNDR4500v3 - if so, this CVE does not apply
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Determine the installed firmware versionAccess the router web interface, navigate to Administration or Advanced settings, and locate the firmware version displayed. This is typically shown on the main status/dashboard page or in a Firmware Update sectionAffected if The installed firmware version is at or above the fixed version for your model: D6100 < 1.0.0.57, R6100 < 1.0.1.20, R7500v2 < 1.0.3.24, WNDR4300v2 < 1.0.0.50, WNDR4500v3 < 1.0.0.50 - versions below these thresholds are affected
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Check if remote web management is enabledIn the router web interface, go to Advanced > Administration > Remote Management or similar section. Look for settings labeled Remote Management, Web Management Access, or Apply WAN Access. Check if any option allows remote (WAN) access to the management interfaceAffected if Remote management is enabled and the router web interface is accessible from the WAN/internet - the vulnerability can be exploited by any unauthenticated network attacker who can reach the device
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Verify network exposure of management interfaceAttempt to access the router login page from an external network using the public IP address, or check router firewall rules that may allow or block inbound HTTP/HTTPS to the WAN interface on ports 80/443Affected if The router management web interface is exposed to unauthenticated users on the network - an attacker does not need credentials to attempt command injection through the vulnerable web interface endpoints
The device is affected if it is one of the five NETGEAR models listed with a firmware version below the specified threshold AND its web management interface is accessible to unauthenticated network 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.
From vendor data1.0.0.501.0.0.571.0.1.20
Update affected devices to the specified firmware versions (D6100: 1.0.0.57, R6100: 1.0.1.20, R7500v2: 1.0.3.24, WNDR4300v2: 1.0.0.50, WNDR4500v3: 1.0.0.50). If updates are unavailable, restrict network access to router management interfaces via firewall rules or disable remote administration.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-21208 — 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-2018-21208 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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- 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
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