I need an existing website to be cleared of bugs and improved

The existing website is PHP and has a database using a custom CMS. The website was hacked and the web provider says the following:

Malware uploaded through a weakness in script on the website.
It is very likely that this is through an outdated CMS you have installed on your web space.

You must:
- Delete files uploaded by hacker
- Change MySQL password
- Change FTP password if FTP has been activated in Control Panel
- Remove weak script or fix weaknesses
- Update all scripts on your website to their latest versions


Please check all your files to make sure the malicious files are all removed.

Once done, please get back to us so we can check and reopen your subscription.

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Can you help? What is your fee for this?

More work in the pipeline...