On one of my pages there are placed wrong links by a backdoor hack. I fix this through a backup of my database. But it's not an appropriate long-dated solution. I have made a SiteChec with https://sitecheck.sucuri.net/ and could find following problems:
Website Malware mwjs-include-pastebin?v1 http://www.biathlon-arena-lenzerheide.ch/arena-betrieb/arena/betriebsgesellschaft/ (View Payload )
SEO Spam MW:SPAM:SEO?gr http://www.biathlon-arena-lenzerheide.ch/arena-betrieb/arena/beschreibung/ ( View Payload )
Website Malware mwjs-include-pastebin?v1 http://www.biathlon-arena-lenzerheide.ch/arena-betrieb/arena/streckenplaene/ ( View Payload )
SEO Spam MW:SPAM:SEO?rb http://www.biathlon-arena-lenzerheide.ch/arena-betrieb/betrieb/ ( View Payload )
How can I solve these problems and how can I protect the page better in the future?