Wireless Lan ControllerOperating system · Cisco
CVE-2020-3559
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 Cisco Aironet Access Point (AP) Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper handling of clients that are trying to connect to the AP. An attacker could exploit this vulnerability by sending authentication requests from multiple clients to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.
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 vulnerability in Cisco Aironet Access Point Software allows an unauthenticated, remote attacker to cause device reload by sending authentication requests from multiple clients. The flaw is due to improper handling of clients trying to connect to the AP.
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
Wireless Lan ControllerOperating system
>= 8.9, < 8.10.112.0
Business Access PointsApplication
>= 10.0, < 10.1.1.0
Access PointsOperating system
< 16.12.4a
Aironet Access Point SoftwareApplication
= 8.5\(151.0\)= 17.2.0.26CVSS 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
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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 the Cisco wireless product typeDetermine if the device is a Cisco Wireless LAN Controller, Cisco Business Access Point, or Cisco Aironet Access Point by checking the device model number or running 'show version' commandAffected if Device is any of these three product types
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Determine the installed software versionRun 'show version' or check the device management interface to obtain the exact software version number installedAffected if Version matches or falls within any of the affected ranges: WLC >= 8.9 and < 8.10.112.0; Business AP >= 10.0 and < 10.1.1.0; AP < 16.12.4a; or Aironet AP version equals 8.5(151.0) or 17.2.0.26
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Verify the device is accepting wireless client connectionsCheck that the AP or WLC has WLANs/SSIDs enabled and clients can associate. Run 'show client summary' or check that radio interfaces are up with 'show interface'Affected if The device has active SSIDs or WLANs configured and is accepting client associations, as the flaw triggers during client authentication attempts
You are affected if you are running any of the listed Cisco wireless products within the specified version ranges and the device is configured to accept client connections.
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 data8.10.112.010.1.1.016.12.4a
Apply the Cisco patch when available. Until then, consider network-level protections such as rate limiting on authentication attempts or intrusion prevention systems to limit suspicious traffic.
Fix this in Wireless Lan Controller
Scoped from the published advisory
- 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-2020-3559 — 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-2020-3559 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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