port scan/probe/communication attempt; port 23

2019-11-30T23:24:31.968449ns386461 sshd\[2174\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=40.112.220.218  user=root
2019-11-30T23:24:34.114541ns386461 sshd\[2174\]: Failed password for root from 40.112.220.218 port 13248 ssh2
2019-11-30T23:41:31.367793ns386461 sshd\[17412\]: Invalid user ssmaru from 40.112.220.218 port 13248
2019-11-30T23:41:31.372752ns386461 sshd\[17412\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=40.112.220.218
2019-11-30T23:41:33.878631ns386461 sshd\[17412\]: Failed password for invalid user ssmaru from 40.112.220.218 port 13248 ssh2
...

Nov 30 23:03:43 sd1 sshd[27226]: Invalid user omsveen from 106.54.53.10
Nov 30 23:03:43 sd1 sshd[27226]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=106.54.53.10
Nov 30 23:03:45 sd1 sshd[27226]: Failed password for invalid user omsveen from 106.54.53.10 port 45188 ssh2
Nov 30 23:15:31 sd1 sshd[27524]: Invalid user berberyan from 106.54.53.10
Nov 30 23:15:31 sd1 sshd[27524]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=106.54.53.10

........
-----------------------------------------------
https://www.blocklist.de/en/view.html?ip=106.54.53.10

port scan/probe/communication attempt; port 23

Nov 30 22:43:36 zx01vmsma01 sshd[200210]: Failed password for root from 113.161.149.47 port 38844 ssh2
...

Apr 13 23:24:08 meumeu sshd[27901]: Failed password for root from 49.76.50.115 port 42200 ssh2
Apr 13 23:24:10 meumeu sshd[27901]: Failed password for root from 49.76.50.115 port 42200 ssh2
Apr 13 23:24:12 meumeu sshd[27901]: Failed password for root from 49.76.50.115 port 42200 ssh2
Apr 13 23:24:15 meumeu sshd[27901]: Failed password for root from 49.76.50.115 port 42200 ssh2
...

SSH Brute Force, server-1 sshd[1804]: Failed password for root from 218.92.0.180 port 8326 ssh2

Nov 30 23:41:48 markkoudstaal sshd[21123]: Failed password for root from 112.85.42.180 port 39962 ssh2
Nov 30 23:41:52 markkoudstaal sshd[21123]: Failed password for root from 112.85.42.180 port 39962 ssh2
Nov 30 23:41:55 markkoudstaal sshd[21123]: Failed password for root from 112.85.42.180 port 39962 ssh2
Nov 30 23:41:58 markkoudstaal sshd[21123]: Failed password for root from 112.85.42.180 port 39962 ssh2

Nov 30 16:27:37 nextcloud sshd\[20569\]: Invalid user spider from 61.218.122.198
Nov 30 16:27:37 nextcloud sshd\[20569\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=61.218.122.198
Nov 30 16:27:39 nextcloud sshd\[20569\]: Failed password for invalid user spider from 61.218.122.198 port 56382 ssh2
...

Nov 30 22:56:57 localhost sshd\[117258\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=222.186.175.163  user=root
Nov 30 22:56:59 localhost sshd\[117258\]: Failed password for root from 222.186.175.163 port 6202 ssh2
Nov 30 22:57:02 localhost sshd\[117258\]: Failed password for root from 222.186.175.163 port 6202 ssh2
Nov 30 22:57:05 localhost sshd\[117258\]: Failed password for root from 222.186.175.163 port 6202 ssh2
Nov 30 22:57:08 localhost sshd\[117258\]: Failed password for root from 222.186.175.163 port 6202 ssh2
...

$f2bV_matches

\[2019-11-30 17:41:54\] NOTICE\[2754\] chan_sip.c: Registration from '"4000" \' failed for '64.31.35.218:6168' - Wrong password
\[2019-11-30 17:41:54\] SECURITY\[2765\] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2019-11-30T17:41:54.732-0500",Severity="Error",Service="SIP",EventVersion="2",AccountID="4000",SessionID="0x7f26c40e0438",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/64.31.35.218/6168",Challenge="178e8b71",ReceivedChallenge="178e8b71",ReceivedHash="6127aa41a395017f4856c39a7389980a"
\[2019-11-30 17:41:54\] NOTICE\[2754\] chan_sip.c: Registration from '"4000" \' failed for '64.31.35.218:6168' - Wrong password
\[2019-11-30 17:41:54\] SECURITY\[2765\] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2019-11-30T17:41:54.815-0500",Severity="Error",Service="SIP",EventVersion="2",AccountID="4000",SessionID="0x7f26c4ab1d88",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/6

Nov 30 22:50:44 localhost sshd\[23215\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=222.186.175.147  user=root
Nov 30 22:50:46 localhost sshd\[23215\]: Failed password for root from 222.186.175.147 port 6588 ssh2
Nov 30 22:50:49 localhost sshd\[23215\]: Failed password for root from 222.186.175.147 port 6588 ssh2
...

Nov  2 15:54:52 server6 sshd[32257]: reveeclipse mapping checking getaddrinfo for 185.8.212.44.ip.uzinfocom.uz [185.8.212.44] failed - POSSIBLE BREAK-IN ATTEMPT!
Nov  2 15:54:52 server6 sshd[32257]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=185.8.212.44  user=r.r
Nov  2 15:54:54 server6 sshd[32257]: Failed password for r.r from 185.8.212.44 port 50646 ssh2
Nov  2 15:54:54 server6 sshd[32257]: Received disconnect from 185.8.212.44: 11: Bye Bye [preauth]
Nov 30 22:55:43 server6 sshd[13486]: reveeclipse mapping checking getaddrinfo for 185.8.212.44.ip.uzinfocom.uz [185.8.212.44] failed - POSSIBLE BREAK-IN ATTEMPT!
Nov 30 22:55:43 server6 sshd[13486]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=185.8.212.44  user=r.r
Nov 30 22:55:45 server6 sshd[13486]: Failed password for r.r from 185.8.212.44 port 48290 ssh2
Nov 30 22:55:45 server6 sshd[13486]: Received disconnect from 185.8.212.44: ........
-------------------------------

Automatic report - Port Scan Attack