This is posted in the Google Ads section, so I assume it refers to Google Ads account suspensions in which the suspension reason shows as due to malicious software, etc. In most such cases, it is due to some coding / hidden coding in the template of the landing page. So, experiment to know about that, by using a simple light template.
In reality there may not be anything malicious, but Google Ads would detect some coding / hidden coding as malicious, so do your experimentations accordingly to narrow down on it.
Sometimes it can also be due to coding / hidden coding in addons in the landing page.