Cisco IOS XR 4.3.4 through 5.3.0 on ASR 9000 devices, when uRPF, PBR, QoS, or an ACL is configured, does not properly handle bridge-group virtual interface (BVI) traffic, which allows remote attackers to cause a denial of service (chip and card hangs and reloads) by triggering use of a BVI interface for IPv4 packets, aka Bug ID CSCur62957.