A vulnerability in the Virtual Private LAN Service (VPLS) code of Cisco IOS 15.0 through 15.4 for Cisco Catalyst 6800 Series Switches could allow an unauthenticated, adjacent attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a denial of service (DoS) condition. The vulnerability is due to a memory management issue in the affected software. An attacker could exploit this vulnerability by creating a large number of VPLS-generated MAC entries in the MAC address table of an affected device. A successful exploit could allow the attacker to cause a C6800-16P10G or C6800-16P10G-XL type line card to crash, resulting in a DoS condition. This vulnerability affects Cisco Catalyst 6800 Series Switches that are running a vulnerable release of Cisco IOS Software and have a Cisco C6800-16P10G or C6800-16P10G-XL line card in use with Supervisor Engine 6T. To be vulnerable, the device must also be configured with VPLS and the C6800-16P10G or C6800-16P10G-XL line card needs to be the core-facing MPLS interfaces. Cisco Bug IDs: CSCva61927.
The HTTP server in Cisco IOS on Catalyst switches does not properly handle TCP socket events, which allows remote attackers to cause a denial of service (device crash) via crafted packets on TCP port (1) 80 or (2) 443, aka Bug ID CSCuc53853.
Unspecified vulnerability in Cisco IOS 12.2SXA, SXB, SXD, and SXF; and the MSFC2, MSFC2a and MSFC3 running in Hybrid Mode on Cisco Catalyst 6000, 6500 and Cisco 7600 series systems; allows remote attackers on a local network segment to cause a denial of service (software reload) via a certain MPLS 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.
Multiple Cisco networking products allow remote attackers to cause a denial of service on the local network via a series of ARP packets sent to the router's interface that contains a different MAC address for the router, which eventually causes the router to overwrite the MAC address in its ARP table.
Cisco Catalyst 6000, 5000, or 4000 switches allow remote attackers to cause a denial of service by connecting to the SSH service with a non-SSH client, which generates a protocol mismatch error.