Cisco Wireless LAN Controller RADIUS Packet of Disconnect Vulnerability

A vulnerability in the RADIUS implementation of the Cisco Wireless LAN Controller (WLC) could allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition by disconnecting user sessions.

The vulnerability is due to a lack of proper input validation of the RADIUS Disconnect-Request packet. An attacker could exploit this vulnerability by sending crafted RADIUS UDP Disconnect-Request packets to the affected device. An exploit could allow the attacker to cause a partial DoS condition due to the disconnect of random user sessions.

Cisco has confirmed the vulnerability; however, software updates are not available.

To exploit this vulnerability, the attacker must send crafted RADIUS Disconnect-Request packets to the targeted system, making exploitation more difficult in environments that restrict network access from untrusted sources.

Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.

Cisco would like to thank security researcher Casper Joost Eyckelhof from Quarantainenet BV for reporting this vulnerability.