I just had the experience that on two of my windows xp prof. pcs the cmdagent took 100% cpu when accessing websites. After uninstalling iTunes the problem was solved. Does anybody had the same problem ?
Achim
Greetings,
Try reading those:
Version 2.4 - cpf.exe and High CPU
https://forums.comodo.com/index.php/topic,6819.0.html
https://forums.comodo.com/index.php/topic,6933.0.html
https://forums.comodo.com/index.php/topic,6943.0.html
Version 2.4 - cmdagent.exe and High CPU
https://forums.comodo.com/index.php/topic,5499.0.html
https://forums.comodo.com/index.php/topic,5972.0.html
https://forums.comodo.com/index.php/topic,6160.0.html
Hope you’ll find a topic that’ll help you 
Cheers,
Ragwing
Yesterday I uninstalled the Comodo Firewall after having it installed for several months/years. This was because the recent update with Defense+. After installing that cmdagent went to 99 percent CPU usage, making the system unusable. Fortunately uninstalling the Comodo Firewall went without any problems.
On these forums I read about disabling logging (make logfile readonly) and/or MDI. However, I could not find this logfile or the place where to disable monitoring DLL injections. So in the end I uninstalled it, because it was not usable anymore. Now I have installed another free firewall solution. That one just works without making the computer unusable.