why is drive wipe writing to my disk

CCleaner for Windows CCleaner Windows Help Requests
1

why is drive wipe writing a file named 3590F75ABA9E485486C100C1A9D4FF06PHQGHUMEAYLNLFDX to my disk when I start a drive wipe of an SD Card.

2

Because it uses the contents of this file to overwrite the unallocated clusters on your storage device, which is what a drive wipe does.