Cisco Wireless LAN Controller (WLC) devices 7.2, 7.3, and 7.4 before 7.4.110.0 allow remote attackers to cause a denial of service (device restart) via a crafted 802.11 Ethernet frame, aka Bug ID CSCuf80681.
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20140305-wlc