Cisco IOS XR 3.8.1 and earlier allows remote authenticated users to cause a denial of service (process crash) via vectors involving a BGP UPDATE message with many AS numbers prepended to the AS path.
Cisco IOS XR 3.6.x, 3.8.x before 3.8.3, and 3.9.x before 3.9.1 does not properly remove sshdlock files from /tmp/, which allows remote attackers to cause a denial of service (disk consumption) by making many SSHv1 connections, aka Bug ID CSCtd64417.
Cisco IOS XR 3.8.1 and earlier allows remote attackers to cause a denial of service (process crash) via a long BGP UPDATE message, as demonstrated by a message with many AS numbers in the AS Path Attribute.
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.
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.
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 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.
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.
Cisco IOS XR through 4.3.2 on Gigabit Switch Router (GSR) 12000 devices does not properly check for a Bidirectional Forwarding Detection (BFD) header in a UDP packet, which allows remote attackers to cause a denial of service (line-card restart) via a crafted packet, aka Bug ID CSCuw56900.
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.