It was the Updraftplus backup plugin i sued and it creates backups on the sever and in my off-site storage location at the same time.
The issue has been resolved though. It was a memory issue alright but the weird thing is that the memory_limit had to be raised all the way to 768MB before the problem stopped. That’s too much even to a beginner like me cos the server gives me just 1GB RAM.
This a new installation and apart from those back-ups still there on the server, notthing else is.
WP Cerber seems to be scanning the whole server, hence its spotting the old backups that are not even on this new installation.
Any advice?