Many of these devices belong to industrial control systems (ICS), building automation, and small enterprise routers. The majority are running firmware from 2008–2012 and have not been patched in over a decade.
After upgrade, verify the new banner (which should be something like SSH-2.0-Cisco-2.0 or SSH-2.0-Cisco-1.99 ). ssh-2.0-cisco-1.25 vulnerability
Older Cisco IOS releases using SSH with TACACS+ authentication are vulnerable to resource exhaustion, which can lead to spontaneous reloads. Scope and Exposure Many of these devices belong to industrial control
: Continued use of CBC-mode ciphers (e.g., aes128-cbc ), which are susceptible to side-channel attacks. How to Secure Your Cisco Device ssh-2.0-cisco-1.25 vulnerability
If the output shows: