Unknown files in file manager

[max321]

I recently had unknown files appear in my file manager at my web host. I looked because when I opened my web page, a virus alert went off. I deleted these mystery files and the virus was gone.

Any idea how someone could insert files on my site and how I can prevent it from happening again?

[WeHostToo]

Check what software you have installed and whether it's the most recent version. If you are running, for example, an old version of WordPress, there are exploits that allow unscrupulous users to get access to your files.