How to protect yourself from viruses?

Question

Backup

I have Eset Smart Security 9, periodically run Dr.Web: CureIt + AVZ. And all the same, somehow sideways, the virus climbed onto the computer and installed itself in the OpenServer project.
How to avoid future infection? How do you protect yourself?

Answer 1

First you need a clear understanding of what a virus is.
The main thing is not to confuse a virus with a malicious program.
That is, a virus may not be malicious and not harm the user, on the other hand, a malicious program may or may not be a virus.
Antivirus programs protect mainly against viruses and partly against malware.
But this is not a panacea.
Protection should be comprehensive and take into account attack vectors.
In your case, an antivirus for Windows is installed, which blocks viruses and some malicious programs running in the Windows environment.
And as far as I understand, the problem arose not with the code executable under Windows, but with the web project that runs on OpenServer, so it is quite logical that antiviruses do not detect it in any way.
The infection most likely occurred due to the ill-conceived security of the web service itself.
That is, you need to protect the web server itself - audit the code, see if any left plugins are used, if there are any potential holes that allow you to organize the execution of the code by your server, by injection.

Answer 2

Is the server local or Web?
If Web, then the reason is:
You don't use frameworks and don't know much at all, so your server can easily be able to upload a PHP file and access it, it would seem that it's scary, just uploading the file, but this is the simplest "shell" through which you can even hack the site!