I am having the same issue. CCleaner wipe has been running for almost 24 hours. The following message appears in the box -
Started erase on disk0s2 Untitled
Creating a temporary file
Securely erasing a file
When I try to get out of the program, I get the following message:
CCleaner cannot be closed until the Erase Free Space operation is complete.
This is a MacBook Air with flash storage.