If you are active in Counter Strike 1.6 Servers these days, you might have noticed a new type of crashing exploit that is being used in wild to crash cs 1.6 servers.
This is a new crashing technique which exploits an Input Validation vulnerability in Counter Strike 1.6 Steam Engine.
Usually you will see multiple players joining with names like #Cstrike_GIGIN_Label or other similar looking nicknmes.
Upon successful exploitation, game of all the players connected to that server is crashed!
To automate the process, Raiz0 has created a tool that sends crafted data packets to target server causing fake player flood in server and as a result all players are crashed or they leave the server due to lag.

How to Fix: (Updated on 16th Feburary, 2015)
To fix the problem, you have to update your Dproto to the latest version.
Download latest Dproto 0.9.524 Version from here.