Cisco IOS XR before 4.2.1 on ASR 9000 series devices and CRS series devices allows remote attackers to cause a denial of service (packet transmission outage) via a crafted packet, aka Bug IDs CSCty94537 and CSCtz62593.

The NETIO and IPV4IO processes in Cisco IOS XR 3.8 through 4.1, as used in Cisco Carrier Routing System and other products, allow remote attackers to cause a denial of service (CPU consumption) via crafted network traffic, aka Bug ID CSCti59888.

The Neighbor Discovery (ND) protocol implementation in the IPv6 stack in Cisco IOS XE 2.1 through 3.17S, IOS XR 2.0.0 through 5.3.2, and NX-OS allows remote attackers to cause a denial of service (packet-processing outage) via crafted ND messages, aka Bug ID CSCuz66542, as exploited in the wild in May 2016.

Cisco IOS XR through 5.3.2 mishandles Local Packet Transport Services (LPTS) flow-base entries, which allows remote attackers to cause a denial of service (session drop) by making many connection attempts to open TCP ports, aka Bug ID CSCux95576.

Cisco IOS XR 5.1 and earlier on Network Convergence System 6000 devices allows remote attackers to cause a denial of service (NPU and card hang or reload) via a malformed MPLS packet, aka Bug ID CSCuq10466.

tacacsd in Cisco IOS XR 5.1 and earlier allows remote attackers to cause a denial of service (process reload) via a malformed TACACS+ packet, aka Bug ID CSCum00468.

Cisco IOS XR 5.1 and earlier allows remote attackers to cause a denial of service (process reload) via a malformed RSVP packet, aka Bug ID CSCuq12031.

snmpd in Cisco IOS XR 5.1 and earlier allows remote authenticated users to cause a denial of service (process reload) via a malformed SNMPv2 packet, aka Bug ID CSCun67791.