I have just released an advisory which can be considered an update of the old rFactor's advisory published exactly one month ago, since the gMotor2 engine used in this game is the same which moves many others:
http://aluigi.org/adv/gmotor2-adv.txt
I premise that I have not performed research specific for each vulnerable game so for the moment the main effects are a crash of the server or the disabling of the UDP port (so nobody can join).
Why this advisory needs a bit of more attention?
Well, because the vulnerable games are the most played racing games of the moment and Race07 has been released less than 2 weeks ago.
The following is the list of games which use gMotor2:
F1 Challenge 99-02, rFactor, GT Legends, GTR, GTR 2, RACE, Race 07, BMW M3 Challenge and possibly others.
Feel free to add more info or tests results here in this thread.
For the moment the only game which SEEMS to be enough safe is F1 99-02.
Race 07 for example crashes with attack 1 and 4, and attack 2 blocks the UDP port.
Almost the same also for Race WTCC and BMW M3 Challenge, except for attack 1.