Fail2ban - Intrusion prevention framework
RdpGuard - RdpGuard allows you to protect your Remote Desktop (RDP), POP3, FTP, SMTP, IMAP, MSSQL, MySQL, VoIP/SIP from brute-force attacks by blocking attacker's IP address. Fail2Ban for Windows.
tallow - Tallow blocks hosts that attempt to bruteforce SSH using the journald API.
Denyhosts - The idea of denying access to SSH servers is nothing new and I was inspired by many other scripts...
SpyLog - Monitor logs from several sources and execute actions based on some rules.
SSHGuard - SSHGuard monitors services through their logging activity.