Reported November 10, 2004, by Cisco
A Denial of Service (DoS) vulnerability exists in Cisco IOS devices running branches of IOS version 12.2S that have DHCP server or relay agent enabled. Certain crafted DHCP packets might be undeliverable but will remain in the queue instead of being dropped. If so many packets are sent that they equal the size of the input queue, no more traffic will be accepted on that interface, resulting in a DoS condition.
Cisco Systems has released Cisco Security Advisory Cisco IOS DHCP Blocked Interface Denial-of-Service to address this vulnerability.
Discovered by Cisco.