Aironet Access Point FirmwareOperating system · Cisco
CVE-2019-1834
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 internal packet processing of Cisco Aironet Series Access Points (APs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected AP if the switch interface where the AP is connected has port security configured. The vulnerability exists because the AP forwards some malformed wireless client packets outside of the Control and Provisioning of Wireless Access Points (CAPWAP) tunnel. An attacker could exploit this vulnerability by sending crafted wireless packets to an affected AP. A successful exploit could allow the attacker to trigger a security violation on the adjacent switch port, which could result in a DoS condition. Note: Though the Common Vulnerability Scoring System (CVSS) score corresponds to a High Security Impact Rating (SIR), this vulnerability is considered Medium because a workaround is available and exploitation requires a specific switch configuration. There are workarounds that address this vulnerability.
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 · moderate confidenceThis vulnerability in Cisco Aironet Series Access Points allows an unauthenticated adjacent attacker to cause DoS by sending crafted wireless packets. The AP incorrectly forwards malformed wireless client packets outside the CAPWAP tunnel, which triggers a security violation on switches with port security enabled, resulting in port shutdown.
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
Aironet Access Point FirmwareOperating system
>= 8.5, < 8.5.140.0>= 8.6.101.0, < 8.8.111.0>= 8.8.120.0, < 8.9.100.0= 8.5\(131.0\)CVSS 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:3.0/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 the device modelLog into the access point and run 'show version' or check the web interface to confirm the device is a Cisco Aironet Series Access PointAffected if The device is not a Cisco Aironet Access Point (not vulnerable)
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Determine the firmware versionRun 'show version' on the AP CLI or check the web interface to display the current firmware versionAffected if The version matches any of these ranges: >= 8.5 and < 8.5.140.0; >= 8.6.101.0 and < 8.8.111.0; >= 8.8.120.0 and < 8.9.100.0; or equals 8.5(131.0)
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Verify switch port security configurationOn the connected switch, run 'show port-security interface <interface>' to check if port security is enabled on the interface connected to the APAffected if Port security is enabled on the switch port connected to the AP
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Check for port security violationsOn the switch, run 'show port-security interface <interface>' to look for security violation counts, and review switch logs for port security violation messagesAffected if Port security violations are occurring on the interface connected to the AP and the AP firmware is in the affected version range
The environment is affected if the Cisco Aironet AP is running a firmware version within the vulnerable ranges AND port security is enabled on the connected switch, which would cause the switch port to shut down when malformed packets are forwarded.
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 data8.5.140.08.8.111.08.9.100.0
Apply available workarounds such as disabling port security on the switch interface connected to the affected AP, or implement packet filtering to block malformed packets before they can trigger the security violation.
Fix this in Aironet Access Point Firmware
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2019-1834 — 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-2019-1834 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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