We had a player come on our forum and say he was banned for no reason. After some debate, I looked in the shrubbot.cfg file and saw that a legitimate ban for a wallhacker was being applied to other players.
The other players had different IP addresses and silent IDs, but all of them had the same userid.
The guy who made the complaint on our forum said he did not even have an etkey, he had reinstalled the game after not playing for a while and attempted to join our server to play with a friend who recommended us to him.
The forum thread is here:
(I go by the name "obituary" on this forum).
I removed the bad bans and updated the server to silent-0.6.1. It had been running silent-0.5.1 when the problem occurred.
All banned players had the same PB ID: CD200BC2