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.

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.

Cisco IOS 12.2 through 12.4 and 15.0 through 15.2 and IOS XE 2.1.x through 2.6.x and 3.1.xS before 3.1.2S, 3.2.xS through 3.4.xS before 3.4.2S, 3.5.xS before 3.5.1S, and 3.1.xSG and 3.2.xSG before 3.2.2SG, when AAA authorization is enabled, allow remote authenticated users to bypass intended access restrictions and execute commands via a (1) HTTP or (2) HTTPS session, aka Bug ID CSCtr91106.

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.

The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

Unspecified vulnerability in Cisco IOS 12.0 through 12.4 allows context-dependent attackers to cause a denial of service (device restart and BGP routing table rebuild) via certain regular expressions in a "show ip bgp regexp" command. NOTE: unauthenticated remote attacks are possible in environments with anonymous telnet and Looking Glass access.

Cisco IOS XR, when configured for Multi Protocol Label Switching (MPLS) and running on Cisco CRS-1 or Cisco 12000 series routers, allows remote attackers to cause a denial of service (Line card crash) via certain MPLS packets, as identified by Cisco bug ID CSCsc77475.

Cisco IOS XR, when configured for Multi Protocol Label Switching (MPLS) and running on Cisco CRS-1 routers, allows remote attackers to cause a denial of service (Modular Services Cards (MSC) crash or "MPLS packet handling problems") via certain MPLS packets, as identified by Cisco bug IDs (1) CSCsd15970 and (2) CSCsd55531.

Cisco IOS 12.0 through 12.4 and IOS XR before 3.2, with IPv6 enabled, allows remote attackers on a local network segment to cause a denial of service (device reload) and possibly execute arbitrary code via a crafted IPv6 packet.