Am 04.02.2014 18:40, schrieb Marc Perkel:
Hope to get some attention about this idea to reduce hacking passwords.
Here is a list of about 700,000 IP addresses that are hacking passwords through SMTP AUTH
http://ipadmin.junkemailfilter.com/auth-hack.txt
This is a list of IP addresses that attempted to authenticate against my fake AUTH advertizing on servers with no authentication. We do front end spam filtering for thousands of domains and I decided to advertize authentication where there is none and I accept and blackhole all authenticated email to those servers. I have harvested the IP addresses in this list that is available through an RBL.
It seems to me that a nice dovecot feature would be the ability to do a black list check against IP addresses connecting and deny access if listed.
Thoughts?
a limit of failed auth-tries without a succesful one would be better and strip down logging after it is blocked instead having thousands of lines from fools trying a dictionary
- ip <xx.xx.xx.xx> blocked after XX auth tries within XX minutes
- blocking of ip <xx.xx.xx.xx> released (XX tries blockd)
something like that but with focus in failed logins
anvil_rate_time_unit = 1800s smtpd_client_connection_rate_limit = 50 smtpd_client_recipient_rate_limit = 400 smtpd_recipient_limit = 100