Corrupted results in search engine query

Hi everyone, new here...

One of the sites my team is working on started showing corrupted search results all of a sudden and seemingly some japanese text started appearing.

I cannot disclose the site at this moment, but someone please tell me what this problem is and how to resolve.

appreciate the help. as per my knowledge its some sort of a malware or cloaking from another site..

Thanks.

Images can be viewed from here: https://drive.google.com/open?id=1WQP7ADqdfkTJAK7IfIMa7GMmwKv_Y4Gp