HIGH
The Smart Install client functionality in Cisco IOS 12.2 and 15.0 through 15.3 on Catalyst switches allows remote attackers to cause a denial of service (device reload) via crafted image list parameters in Smart Install packets, aka Bug ID CSCub55790.
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130327-smartinstall