Wireless Lan Controller FirmwareOperating system · Cisco
CVE-2016-9219
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 with IPv6 UDP ingress packet processing in Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause an unexpected reload of the device. The vulnerability is due to incomplete IPv6 UDP header validation. An attacker could exploit this vulnerability by sending a crafted IPv6 UDP packet to a specific port on the targeted device. An exploit could allow the attacker to impact the availability of the device as it could unexpectedly reload. This vulnerability affects Cisco Wireless LAN Controller (WLC) running software version 8.2.121.0 or 8.3.102.0. Cisco Bug IDs: CSCva98592.
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 Wireless LAN Controller (WLC) Software allows unauthenticated remote attackers to cause device reload by sending crafted IPv6 UDP packets to specific ports. The root cause is incomplete IPv6 UDP header validation during packet processing. Successful exploitation results in denial of service via unexpected device reload.
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 Controller FirmwareOperating system
= 8.2.121.0
Wireless Lan Controller SoftwareOperating system
= 8.3.102.0CVSS 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
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.0/AV:N/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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Determine the Cisco WLC firmware versionLog into the WLC CLI and run 'show version' or access the web interface to view the Controller > Software Version fieldAffected if The displayed version is exactly 8.2.121.0 or exactly 8.3.102.0
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Determine the Cisco WLC software versionLog into the WLC CLI and run 'show version' or access the web interface to view the Software Version fieldAffected if The displayed version is exactly 8.2.121.0 or exactly 8.3.102.0 (for firmware-based installations)
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Verify if IPv6 is enabled on the WLCRun 'show ipv6 status' in the WLC CLI or check the IPv6 settings under Controller > IPv6 in the web interfaceAffected if IPv6 is enabled and the WLC is processing IPv6 traffic (the vulnerability requires IPv6 UDP packets to reach the device)
You are affected only if your WLC runs exactly version 8.2.121.0 or 8.3.102.0 AND IPv6 is enabled on the controller.
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 software update addressing this vulnerability. Upgrade to a patched version beyond 8.2.121.0 or 8.3.102.0 as specified in Cisco's advisory. Consider implementing network segmentation and firewall rules to restrict IPv6 UDP traffic to the WLC management interfaces as a compensating control.
Fix this in Wireless Lan Controller Firmware
Scoped from the published advisory
- Consultation3.0 h
- Implementation4.0 h
- Testing6.0 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 $4,128.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-9219 — 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-2016-9219 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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