The DHCPv6 server in Cisco IOS on ASR 9000 devices with software 5.2.0 Base allows remote attackers to cause a denial of service (process reset) via crafted packets, aka Bug ID CSCun72171.

Cisco ASR 9000 devices with software 5.3.0.BASE do not recognize that certain ACL entries have a single-host constraint, which allows remote attackers to bypass intended network-resource access restrictions by using an address that was not supposed to have been allowed, aka Bug ID CSCur28806.

Cisco IOS XR on ASR 9000 devices does not properly use compression for port-range and address-range encoding, which allows remote attackers to bypass intended Typhoon line-card ACL restrictions via transit traffic, aka Bug ID CSCup30133.

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.

Cisco IOS XR 4.3(.2) and earlier on ASR 9000 devices does not properly perform NetFlow sampling of IP packets, which allows remote attackers to cause a denial of service (chip and card hangs) via malformed (1) IPv4 or (2) IPv6 packets, aka Bug ID CSCuo68417.

Cisco IOS XR 4.3.4 and earlier on ASR 9000 devices, when bridge-group virtual interface (BVI) routing is enabled, allows remote attackers to cause a denial of service (chip and card hangs) via a series of crafted MPLS packets, aka Bug ID CSCuo91149.

Cisco IOS XR on Trident line cards in ASR 9000 devices lacks a static punt policer, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted packets, aka Bug ID CSCun83985.

Cisco IOS XR 4.1.2 through 5.1.1 on ASR 9000 devices, when a Trident-based line card is used, allows remote attackers to cause a denial of service (NP chip and line card reload) via malformed IPv6 packets, aka Bug ID CSCun71928.