Hello folk,
Same issue faced. Here is the screenshot : (the value is changing all the time so it is difficult to catch the higher value but sometimes it reach 16%)

It seems that it is COMODO Internet Security Helper Service that use the CPU, even when I close the COMODO Firewall (I'm not able to terminate the helper service).
Hope that will help to solve the bug.
And my uptime is about 8 days.
Thank you!