I got an alert from Google Webmasters. They say the following file was present in my host:

example.com/~jhostgop/identity.php

I checked my files and it never existed at all.

I've experience this problem in two different host and domains but the file never existed in my file system.

It appears somebody out there is linking a random domain and it prefixes the link with /~jhostgop/identity.php. Now Google may have indexed them so now I get those false phishing alerts.

Anyone experienced this? Is it possible to prevent this?