Cisco Security Advisory – A vulnerability in the Authentication, Authorization, and Accounting (AAA) service for remote Secure Shell Host (SSH) connections to the device for Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause the vulnerable device to reload. The vulnerability is due to an error log message when a remote SSH connection to the device fails AAA authentication. An attacker could exploit this vulnerability by attempting to authenticate to the targeted device. An exploit could allow the attacker to cause a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There is a workaround that addresses this vulnerability.