Cisco IOS Invalid DLSw Handshake Denial of Service

Affected Products

Cisco Internetworking Operating System

Data Link Switching is primarily used for transporting SNA communications across an IP network. Support for this protocol is provided by Cisco networking devices as part of IOS although it is not enabled by default. In specific configurations an attacker could use the DLSw service to trigger a reload of the router’s configuration resulting in a Denial of Service condition.