Miscellaneous first checks
Affected Component(s)
fail2ban is not actually invoking any iptables or equivalent ban
What happened and when does this occur?
Although I can add custom ip's and ranges to be blocked using ./setup.sh fail2ban ban 123.123.0.0/16 the range is not actually being blocked.
#Fail2ban-client status custom
Status for the jail: custom
|- Filter
| |- Currently failed: 0
| |- Total failed: 0
| `- File list:
`- Actions
|- Currently banned: 2
|- Total banned: 2
`- Banned IP list: 141.98.0.0/16 45.125.0.0/16
However in the standard logs:
Jun 29 12:56:04 mail postfix/submission/smtpd[2368]: warning: hostname good-server.outreachratio.com does not resolve to address 141.98.10.70: Name or service not known
Jun 29 12:56:04 mail postfix/submission/smtpd[2368]: connect from unknown[141.98.10.70]
Jun 29 12:56:05 mail postfix/submission/smtpd[2368]: Anonymous TLS connection established from unknown[141.98.10.70]: TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)
Jun 29 12:56:05 mail dovecot: auth: passwd-file(scans,141.98.10.70): unknown user (SHA1 of given password: 5baa61)
Jun 29 12:56:07 mail postfix/submission/smtpd[2368]: warning: unknown[141.98.10.70]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Jun 29 12:56:07 mail postfix/submission/smtpd[2368]: disconnect from unknown[141.98.10.70] ehlo=2 starttls=1 auth=0/1 quit=1 commands=4/5
What did you expect to happen?
I can see that ip: 141.98.10.70 is still able to connect and try to authenticate.
How do we replicate the issue?
1. Deploy mailserver and watch the logs for disctionary attacks.
2.
3.
...
DMS version
latest
What operating system is DMS running on?
Linux
What instruction set architecture is DMS running on?
x86_64 / AMD64
What container orchestration tool are you using?
Docker Compose
docker-compose.yml
version: "3.3"
services:
mailserver:
image: docker.io/mailserver/docker-mailserver:latest
container_name: mailserver
# If the FQDN for your mail-server is only two labels (eg: example.com),
# you can assign this entirely to `hostname` and remove `domainname`.
hostname: mail
domainname: <<redacted>>
env_file: mailserver.env
# More information about the mail-server ports:
# https://docker-mailserver.github.io/docker-mailserver/edge/config/security/understanding-the-ports/
# To avoid conflicts with yaml base-60 float, DO NOT remove the quotation marks.
ports:
- "25:25" # SMTP (explicit TLS => STARTTLS)
- "143:143" # IMAP4 (explicit TLS => STARTTLS)
- "465:465" # ESMTP (implicit TLS)
- "587:587" # ESMTP (explicit TLS => STARTTLS)
- "993:993" # IMAP4 (implicit TLS)
volumes:
- ./docker-data/dms/mail-data/:/var/mail/
- ./docker-data/dms/mail-state/:/var/mail-state/
- ./docker-data/dms/mail-logs/:/var/log/mail/
- ./docker-data/dms/config/:/tmp/docker-mailserver/
- ./docker-data/dms/fail2ban/jail.d/:/etc/fail2ban/jail.d
- /etc/localtime:/etc/localtime:ro
- /etc/letsencrypt/:/etc/letsencrypt/
environment:
- OVERRIDE_HOSTNAME=mail.<<redacted>>
- ENABLE_FAIL2BAN=1
- SSL_TYPE=letsencrypt
restart: always
stop_grace_period: 1m
cap_add:
- NET_ADMIN
healthcheck:
test: "ss --listening --tcp | grep -P 'LISTEN.+:smtp' || exit 1"
timeout: 3s
retries: 0
Relevant log output
Jun 29 12:56:04 mail postfix/submission/smtpd[2368]: warning: hostname good-server.outreachratio.com does not resolve to address 141.98.10.70: Name or service not known
Jun 29 12:56:04 mail postfix/submission/smtpd[2368]: connect from unknown[141.98.10.70]
Jun 29 12:56:05 mail postfix/submission/smtpd[2368]: Anonymous TLS connection established from unknown[141.98.10.70]: TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)
Jun 29 12:56:05 mail dovecot: auth: passwd-file(scans,141.98.10.70): unknown user (SHA1 of given password: 5baa61)
Jun 29 12:56:07 mail postfix/submission/smtpd[2368]: warning: unknown[141.98.10.70]: SASL LOGIN authentication failed: UGFzc3dvcmQ6
Jun 29 12:56:07 mail postfix/submission/smtpd[2368]: disconnect from unknown[141.98.10.70] ehlo=2 starttls=1 auth=0/1 quit=1 commands=4/5
Other relevant information
No response
What level of experience do you have with Docker and mail servers?
Code of conduct
Improvements to this form?
No response
Miscellaneous first checks
Affected Component(s)
fail2ban is not actually invoking any iptables or equivalent ban
What happened and when does this occur?
What did you expect to happen?
How do we replicate the issue?
DMS version
latest
What operating system is DMS running on?
Linux
What instruction set architecture is DMS running on?
x86_64 / AMD64
What container orchestration tool are you using?
Docker Compose
docker-compose.yml
Relevant log output
Other relevant information
No response
What level of experience do you have with Docker and mail servers?
Code of conduct
Improvements to this form?
No response