"There were occurrences of Lish passwords in clear text in our database."

I think that this is what's most criminal about the whole event. It's probably safe to assume that "there were occurances of Lish passwords in clear text..." is a euphemism for "we stored all Lish passwords in cleartext."

Simply invalidating these is probably not enough. It's very likely that people reused their root login passwords as their Lish passwords, meaning that Linodes running without firewalled sshd are potentially vulnerable.

I hope Linode communicated who had "the occurrences" of compromised cleartext Lish passwords, so that those users could take appropriate action.