Cisco Internetwork Operating System (IOS) 12.0S through 12.3T attempts to process SNMP solicited operations on improper ports (UDP 162 and a randomly chosen UDP port), which allows remote attackers to cause a denial of service (device reload and memory corruption).
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5845
https://exchange.xforce.ibmcloud.com/vulnerabilities/15921
http://www.us-cert.gov/cas/techalerts/TA04-111B.html
http://www.securityfocus.com/bid/10186
http://www.kb.cert.org/vuls/id/162451
http://www.cisco.com/warp/public/707/cisco-sa-20040420-snmp.shtml