Cisco IOS 12.0, 12.2, 12.4, 15.0, 15.1, 15.2, and 15.3 and IOS XE 2.x and 3.x before 3.7.4S; 3.2.xSE and 3.3.xSE before 3.3.2SE; 3.3.xSG and 3.4.xSG before 3.4.4SG; and 3.8.xS, 3.9.xS, and 3.10.xS before 3.10.1S allow remote attackers to cause a denial of service (device reload) via malformed RSVP packets, aka Bug ID CSCui11547.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.