oh, I meant the anticheat added in yesterday's update. Since no one has reported anything IDK if it actually works or not. Yeah private servers are definitely safe, just because it lets you forcefully disconnect anyone..there are still some bugs in there that need to be ironed out though.
I'm playing atm with 2015-06-26 and the Anticheat doesn't work. For example: when a HyperMega-Cannon joins and uses it's AHSS gun, there doesn't happen anything.
About the RiceCancer mod, i experienced it 3 times, when hosting a pvp room.
When RiceCancer joins your room, it takes about ~1-3 seconds and then it spams a lot titans at random places and kills them (seen with minimap), which makes the text with "<name> <damage> <titan>" in the middle of the screen to overflow and to crash.