• Our team is looking to connect with folks who use email services provided by Plesk, or a premium service. If you'd like to be part of the discovery process and share your experiences, we invite you to complete this short screening survey. If your responses match the persona we are looking for, you'll receive a link to schedule a call at your convenience. We look forward to hearing from you!
  • We are looking for U.S.-based freelancer or agency working with SEO or WordPress for a quick 30-min interviews to gather feedback on XOVI, a successful German SEO tool we’re looking to launch in the U.S.
    If you qualify and participate, you’ll receive a $30 Amazon gift card as a thank-you. Please apply here. Thanks for helping shape a better SEO product for agencies!
  • The BIND DNS server has already been deprecated and removed from Plesk for Windows.
    If a Plesk for Windows server is still using BIND, the upgrade to Plesk Obsidian 18.0.70 will be unavailable until the administrator switches the DNS server to Microsoft DNS. We strongly recommend transitioning to Microsoft DNS within the next 6 weeks, before the Plesk 18.0.70 release.
  • The Horde component is removed from Plesk Installer. We recommend switching to another webmail software supported in Plesk.

Input Fail2ban was not detecting SASL

tkalfaoglu

Silver Pleskian
I noticed thousands of brute force attacks that were not detected by fail2ban when I did a journalctl -f

Please ensure that

Dec 2 03:52:38 jedi postfix/smtpd[49188]: warning: unknown[193.56.28.139]: SASL LOGIN authentication failed: authentication failure

blurbs are trapped by your fail2ban.. Mine were not..
I just created a new filter and jail definitions..
 
I'm not sure about this.. Every IP has 5 attempts before being blocked by Fail2Ban. Are you sure you are not seen the first 4 attempts for each IP?

Fail2Ban just work fine in Plesk.
 
I'm not sure about this.. Every IP has 5 attempts before being blocked by Fail2Ban. Are you sure you are not seen the first 4 attempts for each IP?
Fail2Ban just work fine in Plesk.

Only for SASL it was not working for me.. For other rules, sure it was working fine..
 
Here is my sasl.conf in jail.d

[sasl]

enabled = true
action = route[name="sasl"]
filter = sasl
logpath = /var/log/maillog
maxretry = 8​

and sasl.conf in filter.d:
PS: I am using a different action that routes the IP to unreachable.


[Definition]

# Option: failregex
# Notes.: regex to match the password failures messages in the logfile. The
# host must be matched by a group named "host". The tag "<HOST>" can
# be used for standard IP/hostname matching and is only an alias for
# (?:::f{4,6}:)?(?P<host>[\w\-.^_]+)
# Values: TEXT

failregex = (?i): warning: [-._\w]+\[<HOST>\]: SASL (?:LOGIN|PLAIN|(?:CRAM|DIGEST)-MD5) au
thentication failed:) [A-Za-z0-9+/ ]*)?$

# Option: ignoreregex
# Notes.: regex to ignore. If this regex matches, the line is ignored.
# Values: TEXT
#
ignoreregex =​
 
Last edited:
Back
Top