As a software developer that operates in the US we’re required by the US Government to comply with US export controls and sanctions. This means that if we recognize that a CCleaner for Android user is in a sanctioned country we must enforce geo-blocking controls so our software cannot be used. When a user is located within a sanctioned country, we must also make sure that our software cannot be updated.
If you are in a sanctioned country and try to download or update CCleaner for Android you will see a message that states that CCleaner is not supported in your current location and you will not be able to proceed. If you are in a sanctioned country while travelling, you will be able to download or update CCleaner for Android once you enter an unrestricted country.
You can find the full list of Office of Foreign Assets Control (OFAC) sanctions here.