CVE-2009-1166: The administrative web interface on the Cisco Wireless LAN Controller (WLC) platform 4.x before 4.2.205.0 a...

Security readout for executives and security teams

A crafted HTTP or HTTPS request to the Cisco WLC administrative web interface can force affected controllers to reload. For organizations still running these legacy WLC versions, the business impact is wireless service disruption, especially where controller availability is critical to campus or branch operations. Exposure is most likely where legacy Cisco WLC administrative web interfaces are reachable over HTTP or HTTPS. Internet-facing or broadly reachable management interfaces raise risk, but the provided sources do not identify default exposure, authentication requirements, or affected deployment prevalence. Treat as a focused availability risk for legacy wireless infrastructure. Prioritize remediation if affected WLCs still support business-critical wireless access or expose management interfaces outside a restricted admin network. Mitigation focus: Upgrade affected WLC 4.x systems to 4.2.205.0 or later where supported.; Upgrade affected WLC 5.x systems to 5.2.191.0 or later where supported.; Review Cisco advisory guidance for platform-specific upgrade paths and operational constraints..

Prepared

Jun 28, 2026, 10:26 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.