CVE-2012-4621
The Device Sensor feature in Cisco IOS 15.0 through 15.2 allows remote attackers to cause a denial of service (device reload) via a DHCP packet, aka Bug ID CSCty96049.
Date published : 2012-09-26
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20120926-dhcp