Cisco Security Advisory – Certain release trains of Cisco Internetwork Operating System (IOS), when configured to use the IOS Secure Shell (SSH) server in combination with Terminal Access Controller Access Control System Plus (TACACS+) as a means to perform remote management tasks on IOS devices, may contain two vulnerabilities that can potentially cause IOS devices to exhaust resources and reload. Repeated exploitation of these vulnerabilities can result in a Denial of Service (DoS) condition. Use of SSH with Remote Authentication Dial In User Service (RADIUS) is not affected by these vulnerabilities.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/37037/cisco-sa-20050406-ssh.txt
Source: https://packetstormsecurity.com/files/37037/Cisco-Security-Advisory-20050406-ssh.html