CVE-2005-1020
HighSummary
A vulnerability in Secure Shell (SSH) 2 in Cisco IOS versions 12.0 through 12.3 allows a remote attacker to cause a denial of service (device reload) through three different scenarios: using a username containing a domain name when authenticating via a TACACS+ server, sending a send command by a logged-in user during the login phase of a new SSH session, or terminating an SSH session while the server is sending data with IOS logging messages.
Risk Assessment
The risk involves the possibility of remotely triggering a device crash, leading to network disruption and potential loss of service access.
Recommendation
It is recommended to upgrade Cisco IOS to a version later than 12.3, which includes fixes for this vulnerability, and consider restricting SSH access to trusted IP addresses.
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Original NVD description (English source)
Secure Shell (SSH) 2 in Cisco IOS 12.0 through 12.3 allows remote attackers to cause a denial of service (device reload) (1) via a username that contains a domain name when using a TACACS+ server to authenticate, (2) when a new SSH session is in the login phase and a currently logged in user issues a send command, or (3) when IOS is logging messages and an SSH session is terminated while the server is sending data.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS