dbcve.org
Wireless Lan ControllerApplication · Cisco

CVE-2015-6311

MEDIUM · 6.1 CVSS v2.0 Published 2015-10-08
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
66/100
Remediation priority · Elevated
No privileges 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
Cisco Wireless LAN Controller (WLC) devices with software 7.0(240.0), 7.3(101.0), and 7.4(1.19) allow remote attackers to cause a denial of service (device outage) by sending malformed 802.11i management data to a managed access point, aka Bug ID CSCub65236.

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

Cisco Wireless LAN Controller devices running versions 7.0(240.0), 7.3(101.0), and 7.4(1.19) contain a vulnerability in the processing of 802.11i management frames. Remote attackers can send malformed 802.11i management data to a managed access point, which triggers a fault condition in the WLC causing the device to crash and require a reboot, resulting in denial of service for all connected wireless clients.

MitigationUpgrade Cisco WLC software to a version that includes the fix for Bug ID CSCub65236 (versions after 7.4(1.19) or as specified in Cisco's advisory). Additionally, restrict management access to trusted networks to reduce attack surface.

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 ControllerApplication
Affected:= 7.0\(240.0\)= 7.3\(101.0\)= 7.4\(1.19\)

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
Authentication
None
Confidentiality
None
Integrity
None
Availability
Complete

AV:A/AC:L/Au:N/C:N/I:N/A:C

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. Confirm device is a Cisco Wireless LAN Controller
    Log into the device and run 'show inventory' or 'show version' to identify the hardware model. Look for product identifiers such as 'Cisco Wireless LAN Controller' or model numbers like AIR-CT, WLC, or 5500/7500 series controllers.
    Affected if The device is not a Cisco Wireless LAN Controller (this CVE only affects WLC devices).
  2. Retrieve the installed software version
    Execute 'show version' on the WLC CLI. The output will display the software version in the format shown (for example, 'Version 7.0(240.0)' or 'Version 7.3(101.0)' or 'Version 7.4(1.19)').
    Affected if The installed version exactly matches 7.0(240.0), 7.3(101.0), or 7.4(1.19).
  3. Verify 802.11i management frame processing is enabled
    Run 'show wlan summary' or 'show run-config' to confirm wireless LANs are configured with WPA2 or 802.11i security policies. The vulnerability triggers when malformed 802.11i management frames are processed.
    Affected if 802.11i or WPA2 wireless networks are configured on the controller (this is the default and required condition for the flaw to be exploitable).
  4. Check if management interface is exposed to untrusted networks
    Review the management interface configuration with 'show run | include mgmt' or 'show interface management'. The attack vector requires sending malformed frames to a managed access point.
    Affected if The management VLAN or interface is reachable from untrusted or external networks (this increases exposure but is not strictly required for the flaw to exist).

You are affected if your Cisco WLC runs exactly version 7.0(240.0), 7.3(101.0), or 7.4(1.19) and has 802.11i/WPA2 wireless networks configured.

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

Upgrade Cisco WLC software to a version that includes the fix for Bug ID CSCub65236 (versions after 7.4(1.19) or as specified in Cisco's advisory). Additionally, restrict management access to trusted networks to reduce attack surface.

Fix this in Wireless Lan Controller Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2015-6311 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2015-6311 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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