• If you are still using CentOS 7.9, it's time to convert to Alma 8 with the free centos2alma tool by Plesk or Plesk Migrator. Please let us know your experiences or concerns in this thread:
    CentOS2Alma discussion

Recent content by ChrisMonder

  1. ChrisMonder

    Question How to ignore/block POP3/IMAP login attempts for a non existent domain in my server?

    Yes, they are plenty of other rules including the one Peter Debik suggested. I tried at first with the A in uppercase. But I got that, the Bad argument '1' Thanks
  2. ChrisMonder

    Question How to ignore/block POP3/IMAP login attempts for a non existent domain in my server?

    Thanks Eliamarsura, I don't use F2B, I use juggernauth firewall, so when I try to run your command, gives me this: iptables: No chain/target/match by that name. And if I change the -l for -a: Bad argument `1' He uses TONS, trust me tons of IP's, and "fresh" ones not listed in blacklists
  3. ChrisMonder

    Question How to ignore/block POP3/IMAP login attempts for a non existent domain in my server?

    I post here again as Peter Debik marked my past post as Resolved, but is not. I have a kind of annoying problem, in the past, my main server IP belong to a very known domain website, they move their website/email server to a new IP range and I got their IP assigned (didn't know about this when I...
  4. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    If you use Postfix with main.cf would be OK. Normally here: /etc/postfix/main.cf
  5. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Hi Rasp, using this lines in config: smtpd_client_restrictions = permit_mynetworks, reject_rbl_client xxxxx.xxxx, permit_sasl_authenticated smtpd_delay_reject = no The xxxxx.xxxx reffers to the block list, I.E.: b.barracudacentral.org
  6. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Or maybe not ;) I figure it our in master.cf commented some lines in submission, and now, I can send email, and I can confirm 100% attacker is being blocked before SASL using the DNSBL Nice christmas gift after months fighting with them. Thanks @danami and have a Happy Christmas !
  7. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    If I do the smtpd_delay_reject = no , then I can't send mail, got this in email client: 5.7.1 Client host rejected: Access denied Below a fragment of maillog of how the attacker tries everytime without problem the SMTP AUTH: Dec 24 01:14:08 sv postfix/smtps/smtpd[12538]: connect from...
  8. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    100% sure. The main.cf and master.cf looks the same
  9. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Well... bad news, it works only for people trying to send mail, not for SASL AUTH/SMTP AUTH, they can still try to login without any problem being listed in the RBL/DNSBL
  10. ChrisMonder

    Resolved How to ignore POP3/IMAP login attempts for a non existent domain in my server?

    Hello @Peter Debik your solution works for a X time, after some hours or days, then stop working and again I need to create the rule, I guess some CRON is deleting it from Iptables or something, I did the iptables-save command, but still deletes it after X time. I´m using CSF and Juggernauth...
  11. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Just to confirm, yes it's working :) Log example: NOQUEUE: reject: RCPT from unknown[XXX.XX.XX.XX]: 554 5.7.1 Service unavailable; Client host [XXX.XX.XX.XX] blocked using (RBL List) Thanks @danami !
  12. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Appears to be working! I will maintain updated about results here, to anyone whishing the same. Thanks @danami
  13. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    I did the steps before mentioned, it slow down the attempts, I still have some. Thanks anyway for your info, don't get me wrong, I just want to know my original question: My original question, is, "is there anyway to use DNSBL block list before SMTP AUTH attempts?" Maybe someone have a...
  14. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    Yes, but I can't enable on 465 or 587. From the article: "Note: Postscreen listens on port 25 only, so authenticated users from port 587 or 465 won’t be affected by Postscreen." From the author: "No. Postscreen only works on port 25. Port 587 is used for SMTP Auth. It’s not used for receiving...
  15. ChrisMonder

    Resolved How to Block SMTP AUTH attempts using a RBL

    No, doesn’t work for my needs, my problem is not spammers, it’s a hacker. Post screen is nice working for 25 port, and spam, but not for before SMTP AUTH, that’s my problem, in SMTP AUTH attempts.
Back
Top