That are plenty of programs to do it around, But as you said no hack, By searching a bit around I found this, Posted by a guy called "Fumz", Credits to him.
Method 1 :
Method 2 :
1. Browse to:
C:\Program Files\Steam\steamapps\common\call of duty modern warfare 2
or for 64bit Windows
C:\Program Files (x86)\Steam\steamapps\common\call of duty modern warfare 2
2. Right Click on the "players" directory and click propeties.
3. Click the "Previous Versions" tab
4. If you have previous versions listed then your in luck.
5. Copy the "players" folder to "Players - Old" so that you have a backup.
6. Delete the contents of the existing "players" folder and copy the files from previous version back in to the dir.
7. Restart MW2.
* Go to the Steam folder and find the Modern Warfare 2 install folder
o Default location: C:\Program Files\Steam\Steamapps\common\call of duty modern warfare 2\
* Open the \players\ folder
* The multiplayer profile is updated regularly as a .stat file and also includes a backup file.
o All original profile files begin with md202ef8d and backup files will begin with md202ef8d.bak
* Locate the profile and backup .stat files with the most recent "Date Modified" listed in Windows
* Move the profile .stat file to a new location (Creating a new folder and placing it here should be fine)
* Rename the backup .stat file and remove the ".bak" from the filename
* Launch Steam and re-test this game.