similar to: under some kind of attack

mj <lists at merit.unu.edu> writes: >>> However, it seems almost all IPs are different, and I don't think I can >>> keep the above settings permanently. >> >> Why not? Limited by firewall rules overload? You could probably use >> a persistent DB, can't you? > > I meant: keep the "block after the first failed attempt" setting.

Hi to all, @Olaf Hopp I've this filter enabled for fail2ban, my question is: could my filters overlap or interfere with those suggested by you? this is my filter: Contents of /etc/fail2ban/jail.conf: [postfix] # Ban for 10 minutes if it fails 6 times within 10 minutes enabled = true port = smtp,ssmtp filter = postfix logpath = /var/log/mail.log maxretry = 6 bantime = 600

> On 26 Jul 2017, at 7:57 pm, Olaf Hopp <Olaf.Hopp at kit.edu> wrote: > > Dear collegues, > > many thanks for your valuable input. > > Since we are an university GEO-IP blocking is not an option for us. > Somestimes I think it should ;-) > > My "mistake" was that I had just *one* fail2ban filter for both cases: > "wrong password" and

Am 18.07.2017 um 22:15 schrieb mj: > Hi, > > Thanks for the quick follow-ups! Much appreciated. After posting this, I > immediately started working on fail2ban. And between my initial posting > and now, fail2ban already blocked 114 IPs. > > I have fail2ban with maxretry=1 and bantime=1800 > > However, it seems almost all IPs are different, and I don't think I can

Hi, Thanks for the quick follow-ups! Much appreciated. After posting this, I immediately started working on fail2ban. And between my initial posting and now, fail2ban already blocked 114 IPs. I have fail2ban with maxretry=1 and bantime=1800 However, it seems almost all IPs are different, and I don't think I can keep the above settings permanently. Robert, your iptables suggestions are

Dear collegues, many thanks for your valuable input. Since we are an university GEO-IP blocking is not an option for us. Somestimes I think it should ;-) My "mistake" was that I had just *one* fail2ban filter for both cases: "wrong password" and "unknown user". Now I have two distinct jails: The first one just for "wrong password" and here the findtime,

Hi Robert, On 07/18/2017 11:43 PM, Robert Schetterer wrote: > i guess not, but typical bots arent using ssl, check it > > however fail2ban sometimes is to slow I have configured dovecot with auth_failure_delay = 10 secs I hope that before the 10 sec are over, dovecot will have logged about the failed login attempt, and fail2ban will have blocked the ip by then. MJ

Olaf Hopp <Olaf.Hopp at kit.edu> writes: > I have dovecot shielded by fail2ban which works fine. But since a few > days I see many many IPs per day knocking on my doors with wron > password and/or users. But the rate at which they are knocking is very > very low. So fail2ban will never catch them. Slow roll distributed attacks. Really hard to stop. > And I see many many

dnsbl's are a popular method to prevent listed ips from making connections to mta software. cf. postscreen_dnsbl_sites in postfix Would it be possible to introduce such a feature in dovecot, so that connections can be denied based on a dnsbl lookup (where the precise dnsbls used are configurable)? John

Hi all, If I may, one more question on this subject: I would like to create a fail2ban filer, that scans for these lines: > Jul 20 11:10:09 auth: Info: ldap(user1,60.166.35.162,<cDFXHbxUQgA8piOi>): invalid credentials (given password: password) > Jul 20 11:10:19 auth: Info: ldap(user2,61.53.66.4,<V+nyHbxU+wA9NUIE>): invalid credentials (given password: password) (as you can

I have concoted something that seems to work. And for the archives, this is it: > failregex = auth: Info: ldap\(.+,<HOST>,.+\): invalid credentials \(given password: .+ssword\) > auth: Info: ldap\(.+,<HOST>,.+\): invalid credentials \(given password: 1qaz2wsx\) > auth: Info: ldap\(.+,<HOST>,.+\): invalid credentials \(given password: 123321\)

I've been running sendmail since the beginning of my online time. 1. Did I see that postfix can run sendmail milters? 2. If so, did I read that postfix can run these separately for inbound vs. outbound? 3. Can it run like a rbl blacklist on inbound and not outbound? 4. If the above is true, does this require separate configurations of postfix or is it already set to allow this out of the

Hi! I have a server running CentOS 7.7 (1908) with all current patches installed. I think this server should be a quite standard installation with no specialities On this server I have fail2ban with an apache and openvpn configuration. I'm using firewalld to manage the firewall rules. Fail2an is configured to use firewalld: [root at server ~]# ll /etc/fail2ban/jail.d/ insgesamt 12

Am 20.07.2017 um 12:28 schrieb mj: > I have concoted something that seems to work. And for the archives, this > is it: > >> failregex = auth: Info: ldap\(.+,<HOST>,.+\): invalid credentials >> \(given password: .+ssword\) >> auth: Info: ldap\(.+,<HOST>,.+\): invalid credentials >> \(given password: 1qaz2wsx\) >> auth:

Hi Olaf, Since we implemented country blocking, everything seems nicely under control, with only 'normal levels' of knocking. We first have impemented: http://blog.jeshurun.ca/technology/block-countries-ubuntu-iptables-xtables-geoip Then we did: https://github.com/firehol/blocklist-ipsets And finale iptables rules like these: > iptables -A INPUT -p tcp --dport 143 -m geoip

On Mon, December 18, 2017 3:06 am, Alex JOST wrote: > Did you enable the dovecot service in fail2ban? By default all jails are > disabled. > > /etc/fail2ban/jail.conf: > [dovecot] > enabled = true Alex, thanks no, not in jail.conf, I've put it in the (1) /etc/fail2ban/jail.local I've also added postfix, that seems to work: I've made test failed dovecot and

From: bounces at isc.sans.edu To: sbradcpa at pacbell.net <sbradcpa at pacbell.net> Novel method for slowing down Locky on Samba server using fail2ban https://isc.sans.edu/diary.html?n&storyid=20805 http://www.heise.de/security/artikel/Erpressungs-Trojaner-wie-Locky-aussperren-3120956.html Google Translate version of above: If you teach the Samba server to monitor and write Rename

Hi folks, "somehow" similar to the thread "under some kind oof attack" started by "MJ": I have dovecot shielded by fail2ban which works fine. But since a few days I see many many IPs per day knocking on my doors with wron password and/or users. But the rate at which they are knocking is very very low. So fail2ban will never catch them. For example one IP: Jul 25

Hello, fail2ban does not ban offending IP. NOTICE[29784] chan_sip.c: Registration from '"user3"<sip:1005 at asterisk-ip:5060>' failed for 'offending-IP:53417' - Wrong password NOTICE[29784] chan_sip.c: Registration from '"user3"<sip:1005 at asterisk-ip:5060>' failed for ?offending-IP:53911' - Wrong password systemctl status

Olaf Hopp <Olaf.Hopp at kit.edu> wrote: > And I have a new one just for "unknown user" and here my bantime and findtime > are much bigger and the retries are just '2'. So here I'm much harsher. > I'll keep an eye on my logs and maybe some more twaeking is necessary. Just be careful about typos (like twaeking!): users could simply misspell their username,