Unspecified vulnerability in the Extensible Authentication Protocol (EAP) implementation in Cisco IOS 12.3 and 12.4 on Cisco Access Points and 1310 Wireless Bridges (Wireless EAP devices), IOS 12.1 and 12.2 on Cisco switches (Wired EAP devices), and CatOS 6.x through 8.x on Cisco switches allows remote attackers to cause a denial of service (device reload) via a crafted EAP Response Identity packet.

Unspecified Cisco Catalyst Switches allow remote attackers to cause a denial of service (device crash) via an IP packet with the same source and destination IPs and ports, and with the SYN flag set (aka LanD). NOTE: the provenance of this issue is unknown; the details are obtained solely from the BID.

Cisco CatOS 5.x before 5.5(20) through 8.x before 8.2(2) and 8.3(2)GLX, as used in Catalyst switches, allows remote attackers to cause a denial of service (system crash and reload) by sending invalid packets instead of the final ACK portion of the three-way handshake to the (1) Telnet, (2) HTTP, or (3) SSH services, aka "TCP-ACK DoS attack."

Cisco Catalyst 4000 series switches running CatOS 5.5.5, 6.3.5, and 7.1.2 do not always learn MAC addresses from a single initial packet, which causes unicast traffic to be broadcast across the switch and allows remote attackers to obtain sensitive network information by sniffing.

Cisco IOS 12.0 through 12.2, when supporting SSH, allows remote attackers to cause a denial of service (CPU consumption) via a large packet that was designed to exploit the SSH CRC32 attack detection overflow (CVE-2001-0144).