You get crossfire hacks here: CrossFire Hacks - MPGH - MultiPlayer Game Hacking
Scroll down, you'll see threads with hacks.
You'll need an injector to 'insert' the hack to crossfire.
You can get injectors in this section: CrossFire Spammers, Injectors and Multi Tools - MPGH - MultiPlayer Game Hacking
Basically, you browse for the hack using the injector (hacks come in a dll), then for the process set it to 'crossfire' .exe (without the ' marks).
Set the injection mode to automatic.
Then open up crossfire.
When crossfire opens, the injector should inject. Close the injector after that.
Enjoy.
Also you need requirements...
.NET Framework 4 and Microsoft Visual C++ 2010 Redistributal.