Dec 23 23:39:47 sd-53420 sshd\[20884\]: User root from 49.235.138.2 not allowed because none of user's groups are listed in AllowGroups
Dec 23 23:39:47 sd-53420 sshd\[20884\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=49.235.138.2  user=root
Dec 23 23:39:49 sd-53420 sshd\[20884\]: Failed password for invalid user root from 49.235.138.2 port 60730 ssh2
Dec 23 23:49:18 sd-53420 sshd\[24278\]: Invalid user nan from 49.235.138.2
Dec 23 23:49:18 sd-53420 sshd\[24278\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=49.235.138.2
...

12/23/2019-17:49:19.657956 185.175.93.105 Protocol: 6 ET SCAN NMAP -sS window 1024

\[2019-12-23 18:08:40\] NOTICE\[2839\] chan_sip.c: Registration from '"704"\' failed for '212.129.30.110:5263' - Wrong password
\[2019-12-23 18:08:40\] SECURITY\[2857\] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2019-12-23T18:08:40.775-0500",Severity="Error",Service="SIP",EventVersion="2",AccountID="704",SessionID="0x7f0fb40aad28",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/212.129.30.110/5263",Challenge="630cb213",ReceivedChallenge="630cb213",ReceivedHash="86e93070005420c3e68651c40747466a"
\[2019-12-23 18:08:43\] NOTICE\[2839\] chan_sip.c: Registration from '"705"\' failed for '212.129.30.110:5320' - Wrong password
\[2019-12-23 18:08:43\] SECURITY\[2857\] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2019-12-23T18:08:43.435-0500",Severity="Error",Service="SIP",EventVersion="2",AccountID="705",SessionID="0x7f0fb4a5a908",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/212

Dec 23 22:40:16 thevastnessof sshd[7334]: Failed password for root from 218.92.0.175 port 37724 ssh2
...

Port scan

Lines containing failures of 136.32.156.194
Dec 23 23:27:53 shared12 sshd[9280]: Invalid user jilda from 136.32.156.194 port 58242
Dec 23 23:27:53 shared12 sshd[9280]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=136.32.156.194
Dec 23 23:27:54 shared12 sshd[9280]: Failed password for invalid user jilda from 136.32.156.194 port 58242 ssh2
Dec 23 23:27:54 shared12 sshd[9280]: Received disconnect from 136.32.156.194 port 58242:11: Bye Bye [preauth]
Dec 23 23:27:54 shared12 sshd[9280]: Disconnected from invalid user jilda 136.32.156.194 port 58242 [preauth]


........
-----------------------------------------------
https://www.blocklist.de/en/view.html?ip=136.32.156.194

Dec 23 23:48:03 localhost postfix/smtpd\[23616\]: warning: unknown\[121.236.158.153\]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Dec 23 23:48:11 localhost postfix/smtpd\[24005\]: warning: unknown\[121.236.158.153\]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Dec 23 23:48:23 localhost postfix/smtpd\[24923\]: warning: unknown\[121.236.158.153\]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Dec 23 23:48:38 localhost postfix/smtpd\[23616\]: warning: unknown\[121.236.158.153\]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Dec 23 23:48:46 localhost postfix/smtpd\[24047\]: warning: unknown\[121.236.158.153\]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
...

2019-12-23T22:47:17.470943abusebot-4.cloudsearch.cf sshd[12943]: Invalid user mysql from 165.22.144.147 port 34340
2019-12-23T22:47:17.476776abusebot-4.cloudsearch.cf sshd[12943]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=165.22.144.147
2019-12-23T22:47:17.470943abusebot-4.cloudsearch.cf sshd[12943]: Invalid user mysql from 165.22.144.147 port 34340
2019-12-23T22:47:19.434642abusebot-4.cloudsearch.cf sshd[12943]: Failed password for invalid user mysql from 165.22.144.147 port 34340 ssh2
2019-12-23T22:49:13.361605abusebot-4.cloudsearch.cf sshd[12948]: Invalid user cehost from 165.22.144.147 port 55290
2019-12-23T22:49:13.367648abusebot-4.cloudsearch.cf sshd[12948]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=165.22.144.147
2019-12-23T22:49:13.361605abusebot-4.cloudsearch.cf sshd[12948]: Invalid user cehost from 165.22.144.147 port 55290
2019-12-23T22:49:15.917600abusebot-4.cloudsearch.cf sshd[12948
...

Dec 23 23:48:52 nextcloud sshd\[618\]: Invalid user webmaster from 49.234.67.23
Dec 23 23:48:52 nextcloud sshd\[618\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=49.234.67.23
Dec 23 23:48:54 nextcloud sshd\[618\]: Failed password for invalid user webmaster from 49.234.67.23 port 53530 ssh2
...

Dec 24 00:11:07 debian-2gb-nbg1-2 kernel: \[795410.838964\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=185.175.93.14 DST=195.201.40.59 LEN=40 TOS=0x00 PREC=0x00 TTL=246 ID=17486 PROTO=TCP SPT=53628 DPT=6418 WINDOW=1024 RES=0x00 SYN URGP=0

Invalid user info from 204.48.19.178 port 40656

Automatic report - SSH Brute-Force Attack

Dec 23 23:01:26 sshgateway sshd\[28504\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=222.186.180.41  user=root
Dec 23 23:01:29 sshgateway sshd\[28504\]: Failed password for root from 222.186.180.41 port 15368 ssh2
Dec 23 23:01:43 sshgateway sshd\[28504\]: error: maximum authentication attempts exceeded for root from 222.186.180.41 port 15368 ssh2 \[preauth\]

Dec 23 23:54:58 debian-2gb-nbg1-2 kernel: \[794441.540493\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=77.247.109.82 DST=195.201.40.59 LEN=436 TOS=0x00 PREC=0x00 TTL=54 ID=0 DF PROTO=UDP SPT=5092 DPT=5060 LEN=416

Dec 24 00:01:49 * sshd[21201]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=185.183.120.29
Dec 24 00:01:52 * sshd[21201]: Failed password for invalid user lavoro from 185.183.120.29 port 35626 ssh2