Cisco IOS XE 3.2 through 3.4 before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR), when VRF-aware NAT and SIP ALG are enabled, allows remote attackers to cause a denial of service (card reload) by sending many SIP packets, aka Bug ID CSCuc65609.