dbcve.org
Aironet Access PointsOperating system · Cisco

CVE-2018-0381

MEDIUM · 6.8 CVSS v3.1 Published 2018-10-17
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
70/100
Remediation priority · Elevated
Zero-click

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 · unedited
A vulnerability in the Cisco Aironet Series Access Points (APs) software could allow an authenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a deadlock condition that may occur when an affected AP attempts to dequeue aggregated traffic that is destined to an attacker-controlled wireless client. An attacker who can successfully transition between multiple Service Set Identifiers (SSIDs) hosted on the same AP while replicating the required traffic patterns could trigger the deadlock condition. A watchdog timer that detects the condition will trigger a reload of the device, resulting in a DoS condition while the device restarts.

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 confidence

This CVE describes a deadlock vulnerability in Cisco Aironet Series Access Points where an authenticated, adjacent attacker can trigger a device reload by transitioning between multiple SSIDs on the same AP while generating specific traffic patterns destined to an attacker-controlled wireless client. The deadlock occurs during dequeue operations of aggregated traffic, triggering a watchdog timer that causes an unexpected reload, resulting in denial of service.

MitigationApply the vendor-supplied software update from Cisco when available. Until then, limit access to trusted users, monitor for unusual SSID transitions, and consider network segmentation to reduce the attack surface for adjacent attackers.

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 PointsOperating system
Affected:= 8.2\(166.0\)= 8.2\(167.3\)= 8.3\(133.0\)= 8.3\(141.10\)= 8.5\(120.0\)= 8.7\(1.96\)= 8.7\(1.99\)= 8.7\(1.107\)

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
Low
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:A/AC:L/PR:L/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify the device model and confirm it is a Cisco Aironet Access Point
    Access the AP CLI and run 'show version' or access the web interface to view device information. Look for 'Aironet' in the product name or model number.
    Affected if The device is not a Cisco Aironet Access Point (not affected)
  2. Check the installed firmware version against the affected versions
    Run 'show version' in the AP CLI and locate the firmware version in the format like 8.2(166.0), 8.2(167.3), 8.3(133.0), 8.3(141.10), 8.5(120.0), 8.7(1.96), 8.7(1.99), or 8.7(1.107). Compare your version exactly to these values.
    Affected if The installed version exactly matches one of these: 8.2(166.0), 8.2(167.3), 8.3(133.0), 8.3(141.10), 8.5(120.0), 8.7(1.96), 8.7(1.99), or 8.7(1.107)
  3. Verify if multiple SSIDs are configured on the AP
    Run 'show run-config' or 'show running-config' in the CLI and look for multiple 'ssid' configurations under the WLAN settings. Alternatively, use 'show wlan summary' to list all configured wireless networks.
    Affected if Two or more SSIDs are configured on the same access point (prerequisite for the attack)
  4. Check for symptoms of unexpected device reloads or watchdog timer events
    Run 'show reload' to see reload history, and review system logs or use 'show logging' to look for watchdog timeout messages, crashinfo entries, or unexpected reload timestamps.
    Affected if The device has experienced unexplained reloads or watchdog timer messages in the logs, especially if correlated with SSID transition activity

The environment is affected if it is a Cisco Aironet AP running exactly one of the listed versions AND has multiple SSIDs configured, particularly if unexplained reloads or watchdog timer events are observed.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the vendor-supplied software update from Cisco when available. Until then, limit access to trusted users, monitor for unusual SSID transitions, and consider network segmentation to reduce the attack surface for adjacent attackers.

Fix this in Aironet Access Points Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2018-0381 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • 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
  • No spam, self-promotion, credentials, or personal data