Mar  6 09:42:45 internal-server-tf sshd\[20202\]: Invalid user oracle from 118.89.38.98Mar  6 09:47:15 internal-server-tf sshd\[20301\]: Invalid user ftpuser from 118.89.38.98
...

2020-03-06 11:29:57 dovecot_plain authenticator failed for \(\[78.128.113.67\]\) \[78.128.113.67\]: 535 Incorrect authentication data \(set_id=harald.schueller@jugend-ohne-grenzen.net\)
2020-03-06 11:30:04 dovecot_plain authenticator failed for \(\[78.128.113.67\]\) \[78.128.113.67\]: 535 Incorrect authentication data \(set_id=harald.schueller\)
2020-03-06 11:31:58 dovecot_plain authenticator failed for \(\[78.128.113.67\]\) \[78.128.113.67\]: 535 Incorrect authentication data \(set_id=harald.schueller@jugend-ohne-grenzen.net\)
2020-03-06 11:32:06 dovecot_plain authenticator failed for \(\[78.128.113.67\]\) \[78.128.113.67\]: 535 Incorrect authentication data \(set_id=harald.schueller\)
2020-03-06 11:35:40 dovecot_plain authenticator failed for \(\[78.128.113.67\]\) \[78.128.113.67\]: 535 Incorrect authentication data \(set_id=harald.schueller@jugend-ohne-grenzen.net\)
...

Mar  6 12:28:20 ift sshd\[802\]: Failed password for root from 222.186.173.154 port 38344 ssh2Mar  6 12:28:24 ift sshd\[802\]: Failed password for root from 222.186.173.154 port 38344 ssh2Mar  6 12:28:27 ift sshd\[802\]: Failed password for root from 222.186.173.154 port 38344 ssh2Mar  6 12:28:30 ift sshd\[802\]: Failed password for root from 222.186.173.154 port 38344 ssh2Mar  6 12:28:34 ift sshd\[802\]: Failed password for root from 222.186.173.154 port 38344 ssh2
...

[Fri Mar 06 11:51:59.916401 2020] [:error] [pid 30070:tid 139858160908032] [client 178.154.171.105:44477] [client 178.154.171.105] ModSecurity: Access denied with code 403 (phase 2). Pattern match "^[\\\\d.:]+$" at REQUEST_HEADERS:Host. [file "/etc/modsecurity/owasp-modsecurity-crs-3.2.0/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] [line "696"] [id "920350"] [msg "Host header is a numeric IP address"] [data "103.27.207.197"] [severity "WARNING"] [ver "OWASP_CRS/3.2.0"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [tag "OWASP_CRS"] [tag "OWASP_CRS/PROTOCOL_VIOLATION/IP_HOST"] [tag "WASCTC/WASC-21"] [tag "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [hostname "103.27.207.197"] [uri "/"] [unique_id "XmHW72gSg3uXizjxuBLcOgAAAUw"]
...

Repeated brute force against a port

Mar  6 05:37:51 ovpn sshd[1736]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=165.22.221.136  user=r.r
Mar  6 05:37:53 ovpn sshd[1736]: Failed password for r.r from 165.22.221.136 port 34750 ssh2
Mar  6 05:37:53 ovpn sshd[1736]: Received disconnect from 165.22.221.136 port 34750:11: Bye Bye [preauth]
Mar  6 05:37:53 ovpn sshd[1736]: Disconnected from 165.22.221.136 port 34750 [preauth]
Mar  6 05:45:52 ovpn sshd[3932]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=165.22.221.136  user=r.r
Mar  6 05:45:53 ovpn sshd[3932]: Failed password for r.r from 165.22.221.136 port 39526 ssh2
Mar  6 05:45:53 ovpn sshd[3932]: Received disconnect from 165.22.221.136 port 39526:11: Bye Bye [preauth]
Mar  6 05:45:53 ovpn sshd[3932]: Disconnected from 165.22.221.136 port 39526 [preauth]
Mar  6 05:51:28 ovpn sshd[5425]: Invalid user steamcmd from 165.22.221.136
Mar  6 05:51:28 ovpn sshd[5425]: pam_unix(sshd........
------------------------------

sshd jail - ssh hack attempt

Email rejected due to spam filtering

42.117.2.174 - - [06/Mar/2020:10:19:52 +0100] "GET /wp-login.php HTTP/1.1" 200 6234 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"
42.117.2.174 - - [06/Mar/2020:10:19:54 +0100] "POST /wp-login.php HTTP/1.1" 200 7133 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"
42.117.2.174 - - [06/Mar/2020:11:19:46 +0100] "GET /wp-login.php HTTP/1.1" 200 5466 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"

Mar  6 06:28:33 web01.agentur-b-2.de postfix/smtpd[513973]: NOQUEUE: reject: RCPT from wandering.swingthelamp.com[69.94.158.122]: 450 4.7.1 : Helo command rejected: Host not found; from= to= proto=ESMTP helo=
Mar  6 06:28:33 web01.agentur-b-2.de postfix/smtpd[513972]: NOQUEUE: reject: RCPT from wandering.swingthelamp.com[69.94.158.122]: 450 4.7.1 : Helo command rejected: Host not found; from= to= proto=ESMTP helo=
Mar  6 06:28:33 web01.agentur-b-2.de postfix/smtpd[522677]: NOQUEUE: reject: RCPT from wandering.swingthelamp.com[69.94.158.122]: 450 4.7.1 : Helo command rejected: Host not found; from= to= proto=ESMTP helo=
Mar  6 06:28:33 web01.agentur-b-2.de postfix/smtpd[519660]: NOQUEUE: reject: RCPT from wandering.swin

Automatic report - Port Scan

Mar  6 05:27:13 mail.srvfarm.net postfix/smtpd[1923012]: NOQUEUE: reject: RCPT from unknown[63.82.48.105]: 450 4.1.8 : Sender address rejected: Domain not found; from= to= proto=ESMTP helo=
Mar  6 05:31:58 mail.srvfarm.net postfix/smtpd[1923012]: NOQUEUE: reject: RCPT from unknown[63.82.48.105]: 450 4.1.8 : Sender address rejected: Domain not found; from= to= proto=ESMTP helo=
Mar  6 05:31:58 mail.srvfarm.net postfix/smtpd[1924628]: NOQUEUE: reject: RCPT from unknown[63.82.48.105]: 450 4.1.8 : Sender address rejected: Domain not found; from= to= proto=ESMTP helo=
Mar  6 05:31:58 mail.srvfarm.net postfix/smtpd[1924638]: NOQUEUE: reject: RCPT from unknown[63.82.48.105]: 450 4.1

CMS (WordPress or Joomla) login attempt.

2020-03-06T10:57:21.171954+01:00 lumpi kernel: [8778451.380414] INPUT:DROP:SPAMHAUS_EDROP:IN=eth0 OUT= MAC=52:54:a2:01:a5:04:d2:74:7f:6e:37:e3:08:00 SRC=185.143.223.97 DST=78.46.199.189 LEN=60 TOS=0x00 PREC=0x00 TTL=54 ID=4526 DF PROTO=TCP SPT=55482 DPT=25 WINDOW=7300 RES=0x00 SYN URGP=0 
...

20/3/5@23:51:56: FAIL: Alarm-Network address from=190.73.254.17
20/3/5@23:51:57: FAIL: Alarm-Network address from=190.73.254.17
...