Udo Rader wrote:
Seth Mattinen schrieb:
Udo Rader wrote:
Udo Rader schrieb:
Hi,
we have recently been hit by a couple of brute force password attacks against dovecot. So what I want to do now is to add dovecot to fail2ban in order to block further attacks.
However, I don't seem to be able to find out password verifification failures for our LDAP based user data.
The only thing I see are loads of lines like these in the logfiles:
-------CUT------- dovecot: Nov 30 09:09:51 Info: pop3-login: Disconnected: user=<ludovic>, method=PLAIN, rip=217.147.235.52, lip=81.16.98.99 dovecot: Nov 30 09:09:51 Info: pop3-login: Disconnected: user=<luna>, method=PLAIN, rip=217.147.235.52, lip=81.16.98.99 dovecot: Nov 30 09:09:51 Info: pop3-login: Disconnected: user=<luke>, method=PLAIN, rip=217.147.235.52, lip=81.16.98.99 -------CUT-------
Googling the web I found that PAM based authentication obviously gives a matchable error message, but for some reasons the ldap backend does not - or does it?
Any pointers highly appreciated :-)
Solved it myself, adding changing to "auth_verbose = yes" in dovecot.conf solved it.
Any reasons why this isn't enabled by default?
Because it's a debugging switch.
hmm, that's weird then.
Without turning on this "debugging switch" (LDAP) authentication failures are not logged, so that's a pretty essential functionality missing then.
You're also running an old version. For me with 1.1.2, "dovecot: imap-login: Aborted login (auth failed, 0 attempts): rip=x.x.x.x, lip=x.x.x.x" is fine. If you want lots of details, turn on debugging.
~Seth