CVE-2020-3428
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 · uneditedA vulnerability in the WLAN Local Profiling feature of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect parsing of HTTP packets while performing HTTP-based endpoint device classifications. An attacker could exploit this vulnerability by sending a crafted HTTP packet to an affected device. A successful exploit could cause an affected device to reboot, resulting in a DoS condition.
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 parsing vulnerability in the WLAN Local Profiling feature of Cisco IOS XE Wireless Controller for Catalyst 9000 series allows an adjacent, unauthenticated attacker to send crafted HTTP packets that trigger incorrect parsing, causing the affected device to reboot and result in a 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 dataall versionsCVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:A/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.
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Identify device model and confirm it is a Catalyst 9000 series wireless controllerRun 'show version' or 'show inventory' command and look for 'C9xxx' in the model number (e.g., C9300, C9400, C9500, C9600) with Wireless Controller capabilityAffected if Device is a Cisco Catalyst 9000 series wireless controller running IOS XE
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Confirm the IOS XE versionRun 'show version' and locate the IOS XE version string (e.g., 16.12.x, 17.3.x, etc.)Affected if The device runs any IOS XE version (all versions are affected)
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Determine if WLAN Local Profiling is enabledRun 'show wireless profile policy summary' or check the wireless policy configuration with 'show running-config | include local-profiling'Affected if WLAN Local Profiling feature is enabled on any wireless policy
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Verify if HTTP server is enabled on the wireless interfaceRun 'show ip http server status' or 'show running-config | include ip http server' to check if HTTP server is activeAffected if HTTP server is enabled (required for the crafted HTTP packet attack vector)
The environment is affected if the device is a Catalyst 9000 series Wireless Controller running IOS XE with WLAN Local Profiling and HTTP server both enabled.
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 the Cisco-provided software patch/update for CVE-2020-3428. As a compensating control, restrict physical/adjacent network access to wireless infrastructure segments.
- Consultation4.0 h
- Implementation6.0 h
- Testing8.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-3428 — 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-2020-3428 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
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