Unspecified vulnerability in Cisco IOS 12.0 through 12.4, IOS XE 2.1.x through 2.3.x before 2.3.2, and IOS XR 3.2.x through 3.4.3, when Multiprotocol Label Switching (MPLS) and Label Distribution Protocol (LDP) are enabled, allows remote attackers to cause a denial of service (device reload or process restart) via a crafted LDP packet, aka Bug IDs CSCsz45567 and CSCsj25893.

Unspecified vulnerability in the sshd_child_handler process in the SSH server in Cisco IOS XR 3.4.1 through 3.7.0 allows remote attackers to cause a denial of service (process crash and memory consumption) via a crafted SSH2 packet, aka Bug ID CSCsu10574.

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 3.8.1 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.

Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.