clamav
https://www.clamav.net/
http://wiki.ubuntu.org.cn/ClamAV
http://blog.topspeedsnail.com/archives/4300
Maldet
https://www.rfxn.com/projects/linux-malware-detect/
rkhunter
http://rkhunter.sourceforge.net/
chkrootkit
http://www.chkrootkit.org/
https://lvtao.net/server/chkrootkit.html
http://www.ywnds.com/?p=6905
http://linux.vbird.org/linux_security/0420rkhunter.php