"php.generic.malware" issue?

Hi, All.

My client just received the following email from their host. Have any of you come across anything similar? Any suggestions for how to deal with it, please?

I should point out that the site was created in 2011 and the CMS/templates haven't been touched since then. Some of the files referred to are specific to this website, but "php.generic.malware" seems to be a common issue on the list. Also, some of the files - indicated in red - are not part of CMSB, nor were they created by me or the client. I've deleted these from the server and that hasn't affected the performance of the site.

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this is a courtesy email to inform you of infected website files under domain nithvalley.com. Netflash recommends the injected files be removed and/or replaced with clean originals. From past contact I understand Nithvalley uses a 3rd party web developer, you may want to forward them this information.

FILE HIT LIST:

{HEX}php.generic.malware.441 : /var/www/vhosts/nithvalley.com/httpdocs/portfolio-commercialDetails.php
{HEX}php.generic.malware.441 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/data/schema/other_projects.ini.php
{HEX}php.generic.malware.441 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/data/schema/services.ini.php
{HEX}php.generic.malware.439 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/uploads/thumb2/files.php
{HEX}php.generic.malware.439 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/uploads/thumb4/db76.php
{HEX}php.generic.malware.439 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/lib/languages/menu57.php
{HEX}php.generic.malware.441 : /var/www/vhosts/nithvalley.com/httpdocs/cmsAdmin/lib/fieldtypes/parentCategory.php
{HEX}php.generic.malware.441 : /var/www/vhosts/nithvalley.com/httpdocs/blogDetails.php
{HEX}php.generic.malware.439 : /var/www/vhosts/nithvalley.com/httpdocs/commercial/start32.php
{HEX}php.generic.malware.439 : /var/www/vhosts/nithvalley.com/httpdocs/institutional/proxy3.php
{HEX}php.base64.v23au.186 : /var/www/vhosts/nithvalley.com/httpdocs/_notes/help.php
{HEX}php.base64.v23au.186 : /var/www/vhosts/nithvalley.com/httpdocs/_mm/ct3beta/messaging/start13.php

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