호스트서버를 년회비 내고 임대해서 쓰고 있는데요,

12월부터 ftp 계정에 
inde.html
index.php

파일을 아래처럼 계속 누가 쓰고 갑니다.
인터넷에서 키워드 검색해 보니 바이러스라고 하는데요....
FTP 호스트 서버 바이러스 검사, 치료는 어떻게 하나요......  예방법도 알려주시면 감사하겠습니다.... ㅠㅠ
그리고 이런 바이러스 걸린 원인은 무엇인가요....

보안상 취약점이 있는거 같은데요.....어떻게 웹페이지도 아니고....FTP 서버파일에 바이러스 걸릴 수 있나요...

<아래는 바이러스라고 합니다....ㅠㅠ>

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