I want to signal an interesting type of problem that affects almost all the videogames with multiplayer support and moreover a resource where finding informations and proof-of-concepts for games and game's engines. I already managed this problem in the past (over one year ago) with Half-Life and then with the Unreal engine but at that time I considered it a "common" bug thinking it wasn't so vast (yeah I was really wrong). The problem is what I call "fake players bug" (I have not found other discussions or papers about the argument so this is the same name I have used the first time) and it is a Denial of Service versus the game servers that host a multiplayer match. I have written a simple paper containing some informations about the problem so I avoid to waste time and space explaining the problem and its effects here. The link for the paper (available also in italian) is: http://aluigi.altervista.org/fakep/fakepintro.txt I have already written proof-of-concepts for some games like Half-Life, the Quake 2 engine, the Quake 3 engine, Serious Sam engine, Unreal 1, Tribes 1 and 2, Need for speed hot pursuit 2, Ghost Recon and others but I update the list continually at least each week: http://aluigi.altervista.org/fakep.htm Have phun --- Luigi Auriemma http://aluigi.altervista.org