dbcve.org
Wireless Lan Controller SoftwareOperating system · Cisco

CVE-2017-12278

MEDIUM · 6.3 CVSS v3.0 Published 2017-11-02
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
69/100
Remediation priority · Elevated
Remotely reachable 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 Simple Network Management Protocol (SNMP) subsystem of Cisco Wireless LAN Controllers could allow an authenticated, remote attacker to cause an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to a memory leak that occurs on an affected device after the device fails to deallocate a buffer that is used when certain MIBs are polled. An attacker who knows the SNMP Version 2 SNMP Read string or has valid SNMP Version 3 credentials for an affected device could repeatedly poll the affected MIB object IDs (OIDs) and consume available memory on the device. When memory is sufficiently depleted on the device, the device will restart, resulting in a DoS condition. Cisco Bug IDs: CSCvc71674.

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

A memory leak vulnerability exists in the SNMP subsystem of Cisco Wireless LAN Controllers where the device fails to deallocate a buffer when certain MIB objects are polled. An authenticated attacker with knowledge of the SNMP read community string or valid SNMPv3 credentials can repeatedly poll specific MIB OIDs, causing memory exhaustion that leads to device restart and DoS.

MitigationRestrict SNMP access to trusted management hosts via ACLs, change SNMP community strings to complex values, and apply the relevant Cisco patch (CSCvc71674) when available.

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 SoftwareOperating system
Affected:all versions

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
Network
Complexity
High
Privileges
Low
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:H/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. Verify SNMP is enabled on the Wireless LAN Controller
    Log into the WLC CLI and run 'show snmp' or access the WLC GUI under Management > SNMP to check if SNMP is enabled
    Affected if SNMP is enabled and accessible means the device could be exploited if the community string is known or guessable
  2. Confirm SNMP read community string configuration
    Run 'show snmp community' in the WLC CLI to list configured community strings
    Affected if Default or simple community strings (such as 'public', 'private', or 'cisco') are in use, making unauthorized access likely
  3. Check network accessibility of SNMP service
    From an external host, attempt to reach the WLC on UDP port 161 (snmpget) using the configured community string to verify SNMP is reachable from untrusted networks
    Affected if SNMP is reachable from management networks that are not explicitly trusted, increasing exposure to attack
  4. Review WLC software version
    Run 'show version' on the WLC CLI or check via GUI under Monitor > Controllers to identify the installed software version
    Affected if All versions of Cisco Wireless LAN Controller Software are affected by this vulnerability when SNMP is enabled
  5. Check for memory exhaustion or unexpected device restarts
    Run 'show system memory' and 'show process memory' on the WLC CLI to monitor available memory; review 'show crash' for any restart history
    Affected if Memory usage is continuously growing or the device has experienced unexplained restarts, which may indicate active exploitation of this memory leak vulnerability

The environment is affected if SNMP is enabled on the WLC and the SNMP read community string or credentials are accessible to an attacker, regardless of software version since all versions are vulnerable.

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

Restrict SNMP access to trusted management hosts via ACLs, change SNMP community strings to complex values, and apply the relevant Cisco patch (CSCvc71674) when available.

Fix this in Wireless Lan Controller Software Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,090
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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-2017-12278 in production — separate from our analysis above.

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What this is

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What belongs here
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