Email rejected due to spam filtering

Mar 22 14:02:55 vpn01 sshd[14518]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=185.220.101.31
Mar 22 14:02:57 vpn01 sshd[14518]: Failed password for invalid user admin from 185.220.101.31 port 36605 ssh2
...

Mar 22 15:07:57 debian-2gb-nbg1-2 kernel: \[7145170.224191\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=92.118.37.91 DST=195.201.40.59 LEN=40 TOS=0x00 PREC=0x00 TTL=64 ID=59634 DF PROTO=TCP SPT=58185 DPT=21 WINDOW=29200 RES=0x00 SYN URGP=0

SSH brute force attempt

Mar 22 14:02:39  sshd\[15848\]: Invalid user students from 139.170.150.252Mar 22 14:02:41  sshd\[15848\]: Failed password for invalid user students from 139.170.150.252 port 29760 ssh2
...

Mar 22 10:01:38 plusreed sshd[16671]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=222.186.30.35  user=root
Mar 22 10:01:40 plusreed sshd[16671]: Failed password for root from 222.186.30.35 port 63035 ssh2
...

$f2bV_matches

2020-03-22 14:44:53 dovecot_login authenticator failed for \(User\) \[92.118.38.42\]: 535 Incorrect authentication data \(set_id=ireland@no-server.de\)
2020-03-22 14:45:27 dovecot_login authenticator failed for \(User\) \[92.118.38.42\]: 535 Incorrect authentication data \(set_id=ireland@no-server.de\)
2020-03-22 14:45:36 dovecot_login authenticator failed for \(User\) \[92.118.38.42\]: 535 Incorrect authentication data \(set_id=ireland@no-server.de\)
2020-03-22 14:48:03 dovecot_login authenticator failed for \(User\) \[92.118.38.42\]: 535 Incorrect authentication data \(set_id=iris@no-server.de\)
2020-03-22 14:48:36 dovecot_login authenticator failed for \(User\) \[92.118.38.42\]: 535 Incorrect authentication data \(set_id=iris@no-server.de\)
...

1584882210 - 03/22/2020 14:03:30 Host: 77.85.224.5/77.85.224.5 Port: 445 TCP Blocked

Unauthorized connection attempt detected from IP address 222.186.30.218 to port 22 [T]

[2020-03-22 10:01:12] NOTICE[1148] chan_sip.c: Registration from '' failed for '185.147.215.12:61088' - Wrong password
[2020-03-22 10:01:12] SECURITY[1163] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2020-03-22T10:01:12.055-0400",Severity="Error",Service="SIP",EventVersion="2",AccountID="5150",SessionID="0x7fd82c40aa58",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/185.147.215.12/61088",Challenge="1b2e4529",ReceivedChallenge="1b2e4529",ReceivedHash="2a29935e330f5bc777531dd756917304"
[2020-03-22 10:01:43] NOTICE[1148] chan_sip.c: Registration from '' failed for '185.147.215.12:65287' - Wrong password
[2020-03-22 10:01:43] SECURITY[1163] res_security_log.c: SecurityEvent="InvalidPassword",EventTV="2020-03-22T10:01:43.022-0400",Severity="Error",Service="SIP",EventVersion="2",AccountID="5033",SessionID="0x7fd82c530768",LocalAddress="IPV4/UDP/192.168.244.6/5060",RemoteAddress="IPV4/UDP/185.147.21
...

Mar 22 16:04:38 www5 sshd\[42887\]: Invalid user play from 73.69.219.82
Mar 22 16:04:38 www5 sshd\[42887\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=73.69.219.82
Mar 22 16:04:40 www5 sshd\[42887\]: Failed password for invalid user play from 73.69.219.82 port 46310 ssh2
...

Mar 22 14:37:54 nextcloud sshd\[25671\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=222.186.169.192  user=root
Mar 22 14:37:56 nextcloud sshd\[25671\]: Failed password for root from 222.186.169.192 port 22174 ssh2
Mar 22 14:38:00 nextcloud sshd\[25671\]: Failed password for root from 222.186.169.192 port 22174 ssh2

Lines containing failures of 217.244.218.74
Mar 22 13:44:25 MAKserver05 sshd[30067]: Invalid user pi from 217.244.218.74 port 58276
Mar 22 13:44:25 MAKserver05 sshd[30067]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=217.244.218.74 
Mar 22 13:44:25 MAKserver05 sshd[30069]: Invalid user pi from 217.244.218.74 port 58278
Mar 22 13:44:25 MAKserver05 sshd[30069]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=217.244.218.74 


........
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https://www.blocklist.de/en/view.html?ip=217.244.218.74

Honeypot attack, port: 81, PTR: PTR record not found