How to remove a virus from hosting?

Question

Malware

I had about 10 sites on my hosting (best-hoster.ru). The first time the hoster blocked my account due to spamming (pointed to the site files on wordpress). I took down all these sites. And everything seems to have calmed down.
But here 2 days ago - again blocking . The reason is the same spamming. But it already refers to files in the html site.
For example: the option.php file appeared in the folder with fonts , the function.php file in the root of the site. The content of the files is as follows:

I moved everything to LAN. And now I'm thinking whether a simple deletion of these files will help to avoid a second "trouble". The hosting told me that this is the last time :)

Answer 1

There are several options here:
1) you didn’t change the passwords for the admin panel and ftp
2) you didn’t clean out all the “living creatures”
3) the host was globally hacked

Answer 2

The host has nothing to do with it.
The file is standard.
It is wise to check all sites for viruses.
Then change passwords to admins, update plugins and CMS version.
Instructions for the treatment of Joomla , but also suitable for other CMS