Cisco IOS XR 4.3(.2) and earlier on ASR 9000 devices does not properly perform NetFlow sampling of packets with multicast destination MAC addresses, which allows remote attackers to cause a denial of service (chip and card hangs) via a crafted packet, aka Bug ID CSCup77750.
Improper Input Validation 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.