Valve is handing out TF2 VAC bans to Linux users with 'catbot' in their username
On the GitHub thread where the issue was uncovered, one user said that their Steam account was VAC banned despite claiming to never have cheated. Another said ''I installed Ubuntu on a virtual machine and named the computer catbot-918 and installed Steam, within an hour of not playing anything i received a VAC ban.''
A GitHub moderator confirmed that the policy was in fact a deliberate attempt to combat bots, adding that it was ''not open for discussion on GitHub''.
UPDATE-
Hi! Valve employee here. The bug report is incorrect. VAC will not ban you for simply having catbot in your user name (either your steam profile or on one or more of your linux accounts).
The bug report--and I suspect many of the posts in this thread--are a tactic employed by cheaters to try and sow discord and distrust among anticheat systems.
VAC has many different types of detections and we cannot discuss what they do publicly because doing so makes them less effective. However, one thing I can disclose is that all detections require that the detection occur while a user is actively cheating and connected to a VAC-secured server.
Linux historically hasn't been a problem for cheating--the base rate of cheating is significantly lower on Linux than it is on Windows. Unfortunately, a "healthy" community of cheaters grew up around catbot on linux and their impact on TF became large enough that they simply could no longer be ignored. Those banned users are very annoyed that VAC has dropped the hammer on them.
Kisak moderates many of valve's github bug repositories for us in an attempt to keep the bugs high quality and actionable. The VAC team asked him to close the issue in question and to indicate that github was not an appropriate location to discuss VAC bans. He did so, and we support this action.
For proof that I am a Valve employee, you can check my posting flair in the other subs I post on (/r/CSGO and /r/tf2) or a mod can message me and we can work on confirmation using my work email and PMs.
