> Disabling the 'backdoor' seems to just involve disabling SSH.

Maybe. My guess these are essentially Linux systems, so if attackers know that their exploits are widely known then they will likely try to figure out ways to install kernel mod rootkits.

It'll then end up in a situation with Windows XP/Vista days were IT desktop support staff would run malware removal tools to get rid of porn pop-ups on desktops only to have "reinfections" pop up a day or week or two later.

They'd blame users for this, but really they just never actually removed the command and control botnet features. They just addressed their payloads. The machines were never actually fixed in the first place.