I've seen a serious multitenant business app that manages financial info do this. Except the credentials were root. And also valid for SSH. Users would run a Ja

I've seen a serious multitenant business app that manages financial info do this. Except the credentials were root. And also valid for SSH. Users would run a Java applet, which would SELECT from users (after connecting as root) to determine if their login was successful. 7-8 figures per install and this was a "known issue".