1561667220 - 06/28/2019 03:27:00 Host: 151.53.230.29/151.53.230.29 Port: 23 TCP Blocked
...

Honeypot attack, port: 23, PTR: 114-40-169-206.dynamic-ip.hinet.net.

Jun 28 18:10:22 vmd17057 sshd\[9659\]: Invalid user test from 35.204.165.73 port 34976
Jun 28 18:10:22 vmd17057 sshd\[9659\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=35.204.165.73
Jun 28 18:10:24 vmd17057 sshd\[9659\]: Failed password for invalid user test from 35.204.165.73 port 34976 ssh2
...

Jun 28 15:44:44 efgeha sshd[6283]: Did not receive identification string from 123.206.76.175
Jun 28 15:45:14 efgeha sshd[6299]: Invalid user geier from 123.206.76.175
Jun 28 15:45:35 efgeha sshd[6303]: Invalid user polycom from 123.206.76.175


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https://www.blocklist.de/en/view.html?ip=123.206.76.175

Jun 28 16:49:59 ip-172-31-1-72 sshd\[2687\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=115.90.219.20  user=root
Jun 28 16:50:01 ip-172-31-1-72 sshd\[2687\]: Failed password for root from 115.90.219.20 port 50976 ssh2
Jun 28 16:52:25 ip-172-31-1-72 sshd\[2695\]: Invalid user kou from 115.90.219.20
Jun 28 16:52:25 ip-172-31-1-72 sshd\[2695\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=115.90.219.20
Jun 28 16:52:26 ip-172-31-1-72 sshd\[2695\]: Failed password for invalid user kou from 115.90.219.20 port 45896 ssh2

TCP port 445 (SMB) attempt blocked by firewall. [2019-06-28 15:45:06]

" "

Jun 25 22:57:47 xb3 sshd[8144]: reveeclipse mapping checking getaddrinfo for host-37-247-108-101.routergate.com [37.247.108.101] failed - POSSIBLE BREAK-IN ATTEMPT!
Jun 25 22:57:49 xb3 sshd[8144]: Failed password for invalid user germaine from 37.247.108.101 port 55700 ssh2
Jun 25 22:57:49 xb3 sshd[8144]: Received disconnect from 37.247.108.101: 11: Bye Bye [preauth]
Jun 25 23:00:13 xb3 sshd[22039]: reveeclipse mapping checking getaddrinfo for host-37-247-108-101.routergate.com [37.247.108.101] failed - POSSIBLE BREAK-IN ATTEMPT!
Jun 25 23:00:15 xb3 sshd[22039]: Failed password for invalid user willy from 37.247.108.101 port 48150 ssh2
Jun 25 23:00:15 xb3 sshd[22039]: Received disconnect from 37.247.108.101: 11: Bye Bye [preauth]
Jun 25 23:03:58 xb3 sshd[10693]: reveeclipse mapping checking getaddrinfo for host-37-247-108-101.routergate.com [37.247.108.101] failed - POSSIBLE BREAK-IN ATTEMPT!
Jun 25 23:04:00 xb3 sshd[10693]: Failed password for invalid user parc from 37........
-------------------------------

[Thu Jun 27 20:30:33.522283 2019] [:error] [pid 15992:tid 139848094512896] [client 177.190.176.21:26954] [client 177.190.176.21] ModSecurity: Access denied with code 403 (phase 2). Pattern match "^[\\\\d.:]+$" at REQUEST_HEADERS:Host. [file "/etc/modsecurity/owasp-modsecurity-crs-3.1.1/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] [line "792"] [id "920350"] [msg "Host header is a numeric IP address"] [data "103.27.207.197:80"] [severity "WARNING"] [ver "OWASP_CRS/3.1.1"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [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 "XRTE@eQ1bEWk@u5l7ODlPQAAABQ"]
...

[Thu Jun 27 14:46:27.452875 2019] [:error] [pid 974:tid 140566293608192] [client 212.66.123.151:49916] [client 212.66.123.151] ModSecurity: Access denied with code 403 (phase 2). Pattern match "^[\\\\d.:]+$" at REQUEST_HEADERS:Host. [file "/etc/modsecurity/owasp-modsecurity-crs-3.1.1/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] [line "792"] [id "920350"] [msg "Host header is a numeric IP address"] [data "103.27.207.197:80"] [severity "WARNING"] [ver "OWASP_CRS/3.1.1"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [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 "XRR0U07jnz5MrDV2AHY-1gAAAA8"]
...

[Thu Jun 27 12:25:38.565576 2019] [:error] [pid 26865:tid 140527362074368] [client 141.8.132.35:59414] [client 141.8.132.35] ModSecurity: Access denied with code 403 (phase 2). Pattern match "^[\\\\d.:]+$" at REQUEST_HEADERS:Host. [file "/etc/modsecurity/owasp-modsecurity-crs-3.1.1/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] [line "792"] [id "920350"] [msg "Host header is a numeric IP address"] [data "103.27.207.197"] [severity "WARNING"] [ver "OWASP_CRS/3.1.1"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [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 "XRRTUhlQuTljWBroxg@h6QAAAAk"]
...

Jun 28 15:05:37 debian sshd\[10645\]: Invalid user danny from 80.28.234.134 port 49845
Jun 28 15:05:37 debian sshd\[10645\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=80.28.234.134
...

ZTE Router Exploit Scanner

Jun 28 15:19:55 debian sshd\[10724\]: Invalid user mz from 112.217.225.59 port 49738
Jun 28 15:19:55 debian sshd\[10724\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=112.217.225.59
...

Jun 28 15:47:31 server postfix/smtpd[11018]: NOQUEUE: reject: RCPT from excellent.ppobmspays.com[5.133.66.146]: 554 5.7.1 Service unavailable; Client host [5.133.66.146] blocked using zen.spamhaus.org; https://www.spamhaus.org/sbl/query/SBLCSS; from= to= proto=ESMTP helo=