Treatment 2 sites from viruses. Check the server for viruses

Good day!

Not long ago, the website/server got a virus that supposedly send you spam on other sites/posts.

My 2 sites are on a dedicated server.

The server comes complaint. The text of the complaint is not displayed.

Im not an expert on viruses, and I cant say exactly what happened. But this is most likely a spam mailing from the website on the engine WordPress.

The first site is running on WordPress (updated to the latest version), the other on Therefore. 3.0

The server is running on fastpanel, the content management system from the server. (Not ispmanager).

P. S. it is Necessary to identify the problem of malicious script/virus or whatever, clean, and supply protection.

Work safe, please offer Your terms and rates for the project.