Modifying a protected file. This just occurred today after opening Cleaner V5.25.5902. Windows 7 64 version. Never had any firewall alerts on Ccleaner before.
Download 5.34 (latest build as of post date) and see if the same happens
Updated to latest version from periform. Rebooted and started Ccleaner watching events. It first reported a registery key modified and then on another restart if reported Ccleaner wanted to modify a file or folder. I'll keep a close eye on this
Well ccleaner does have the power of modifying files (deleting some outright and emptying database and data) and folders as well as registry keys (in registry cleaning and regular cleaning) so both those warnings make sense to me for ccleaner's use