The TCL shell in Cisco IOS 12.2(14)S before 12.2(14)S16, 12.2(18)S before 12.2(18)S11, and certain other releases before 25 January 2006 does not perform Authentication, Authorization, and Accounting (AAA) command authorization checks, which may allow local users to execute IOS EXEC commands that were prohibited via the AAA configuration, aka Bug ID CSCeh73049.

Multiple unspecified vulnerabilities in the Internet Key Exchange version 1 (IKEv1) implementation in multiple Cisco products allow remote attackers to cause a denial of service (device reset) via certain malformed IKE packets, as demonstrated by the PROTOS ISAKMP Test Suite for IKEv1. NOTE: due to the lack of details in the Cisco advisory, it is unclear which of CVE-2005-3666, CVE-2005-3667, and/or CVE-2005-3668 this issue applies to.

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.

Secure Shell (SSH) 2 in Cisco IOS 12.0 through 12.3 allows remote attackers to cause a denial of service (device reload) (1) via a username that contains a domain name when using a TACACS+ server to authenticate, (2) when a new SSH session is in the login phase and a currently logged in user issues a send command, or (3) when IOS is logging messages and an SSH session is terminated while the server is sending data.

Cisco IOS 12.0S through 12.3YH allows remote attackers to cause a denial of service (device restart) via a crafted IPv6 packet.

Memory leak in Secure Shell (SSH) in Cisco IOS 12.0 through 12.3, when authenticating against a TACACS+ server, allows remote attackers to cause a denial of service (memory consumption) via an incorrect username or password.

Cisco IOS 12.0 through 12.3YL, with BGP enabled and running the bgp log-neighbor-changes command, allows remote attackers to cause a denial of service (device reload) via a malformed BGP packet.

IP Security VPN Services Module (VPNSM) in Cisco Catalyst 6500 Series Switch and the Cisco 7600 Series Internet Routers running IOS before 12.2(17b)SXA, before 12.2(17d)SXB, or before 12.2(14)SY03 could allow remote attackers to cause a denial of service (device crash and reload) via a malformed Internet Key Exchange (IKE) packet.

OpenSSL 0.9.6k allows remote attackers to cause a denial of service (crash via large recursion) via malformed ASN.1 sequences.

Cisco IOS 11.x and 12.0 through 12.2 allows remote attackers to cause a denial of service (traffic block) by sending a particular sequence of IPv4 packets to an interface on the device, causing the input queue on that interface to be marked as full.