how are you loading sourcebans on your server... also how are you loading sourcemod on your server.

this is from the KAC logs:
L 03/16/2009 - 19:48:37: JohnMothaFcknRyan (STEAM_0:1:1353053 attempted to exploit this server with: changelevel "ma_say;rcon_password hacker".

so KAC does detect it.

i dont run those rcon cvars in my server configs at all so that might be why its working for me and not you.

siosios