CVE-2005-1020

CVE-2005-1020 describes a denial-of-service vulnerability in Cisco IOS versions 12.0 through 12.3 when using Secure Shell (SSH) 2. This flaw allows remote attackers to cause a device reload through specific actions, such as providing a domain-containing username during TACACS+ authentication, initiating a new SSH session while another user issues a "send" command, or terminating an SSH session while the server is sending logged messages. The vulnerability carries a CVSS score of 7.1, indicating high severity, with a network attack vector and medium attack complexity. A successful exploit leads to a complete loss of availability for the affected device. Despite its severity, there is no evidence of active exploitation, no known public exploit code (Metasploit, Nuclei, ExploitDB), and minimal community discussion or media coverage surrounding this CVE.