aaPanel_Kern
I notice that if i restart the Apache, i`m getting an error:
Apache rule configuration error:
AH00526: Syntax error on line 8 of /www/server/panel/vhost/apache/mydomain.conf:
CustomLog takes two or three arguments, a file name, a custom log format string or format name, and an optional "env=" or "expr=" clause (see docs)

    some hacker is sending emails from root@mydomain and root@locahost

    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 4E8C6160062A: removed
    May 5 15:46:28 vmi613070 postfix/local[18768]: C56E71601880: to=<root@localhost>, relay=local, delay=16772, delays=16772/0.52/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: C56E71601880: removed
    May 5 15:46:28 vmi613070 postfix/local[18765]: 0CBA3160072E: to=<root@localhost>, relay=local, delay=26749, delays=26748/0.52/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 0CBA3160072E: removed
    May 5 15:46:28 vmi613070 postfix/local[18768]: 9DB4D160059E: to=<root@localhost>, relay=local, delay=9583, delays=9583/0.53/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 9DB4D160059E: removed
    May 5 15:46:28 vmi613070 postfix/local[18767]: 3FCC816007A7: to=<root@localhost>, relay=local, delay=23291, delays=23290/0.53/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 3FCC816007A7: removed
    May 5 15:46:28 vmi613070 postfix/local[18765]: C346B1600552: to=<root@localhost>, relay=local, delay=34139, delays=34139/0.54/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: C346B1600552: removed
    May 5 15:46:28 vmi613070 postfix/local[18768]: B9B1D16000EB: to=<root@localhost>, relay=local, delay=34140, delays=34139/0.54/0/0.01, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: B9B1D16000EB: removed
    May 5 15:46:28 vmi613070 postfix/local[18765]: 95BCF160149C: to=<root@localhost>, relay=local, delay=4029, delays=4029/0.55/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 95BCF160149C: removed
    May 5 15:46:28 vmi613070 postfix/local[18767]: AFAAE1600113: to=<root@localhost>, relay=local, delay=28708, delays=28708/0.55/0/0.01, dsn=2.0.0, status=sent (delivered to mailbox)
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: AFAAE1600113: removed
    May 5 15:46:29 vmi613070 postfix/local[18766]: B222B1601485: to=<root@localhost>, relay=local, delay=21982, delays=21981/0.03/0/0.91, dsn=2.0.0, status=sent (delivered to mailbox)
    .....
    May 5 15:46:28 vmi613070 postfix/master[18761]: daemon started -- version 3.4.7, configuration /etc/postfix
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: warning: /etc/postfix/main.cf, line 707: overriding earlier entry: myhostname=mail.mydomain.com
    May 5 15:46:28 vmi613070 postfix/pickup[18762]: warning: /etc/postfix/main.cf, line 707: overriding earlier entry: myhostname=mail.mydomain.com
    May 5 15:46:28 vmi613070 postfix/qmgr[18763]: 8361616007ED: from=root@vmi613070.hostingdomain.com, size=493, nrcpt=1 (queue active)
    May 5 15:46:28 vmi613070 postfix/trivial-rewrite[18764]: warning: /etc/postfix/main.cf, line 707: overriding earlier entry: myhostname=mail.mydomain.com

    What is the best way to block it?

      aaP_esales2000
      In the Linux system, the root user can send emails by default. However, in order to enhance system security, you can restrict the root user from sending mail by configuring the mail server or changing the settings of the mail client.

      Here are some ways you can restrict the root user from sending mail:

      Configure mail server: You can configure mail server to prevent root user from sending mail. Specifically, you can create a mail filtering rule on the mail server to prevent the root user from sending mail. For example, in a Postfix mail server, you would add the following to the /etc/postfix/main.cf file:

      smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access

      Then, add the following to the /etc/postfix/sender_access file:

      root REJECT

      This will change mailx's default sender address, preventing root from sending mail.

      Change the email address of the root user: You can change the email address of the root user to prevent the root user from sending emails. For example, on an Ubuntu system, you can edit the /etc/aliases file and change root's email address to a non-real email address:

      root: /dev/null

      This will prevent the root user from sending mail.
      Note that changing the configuration of the root user may affect the normal operation of the system. Therefore, make sure you know what you are doing and back up important data before changing your system configuration.

        When i use
        smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access

        Im receiving an error while trying to send emails from the primary email account that Im using on my WordPress (info@mydomain.com).
        when I remove the sender restrict option from the config file. then it's working again and I can send emails from info@mydomain.com.
        i didn't check yet if this issue is with all email accounts.

        Mailer: Other SMTP
        SMTP Error: The following recipients failed: someemailaddress@gmail.com: : Sender address rejected: Server configuration error

          Is it possible to send after cancellation?
          It is recommended to check whether the sender email configuration of wordpress is misconfigured?
          Also check whether the ssl of the mail server is configured correctly?
          "mail.135mailtest.com" is replaced with your domain name
          You can use this command to check whether the correct SSL is configured
          openssl s_client -connect mail.135mailtest.com:587 -starttls smtp
          or
          openssl s_client -connect mail.135mailtest.com:465 -starttls smtp

          If the display is not OK, please re-apply for SSL

          aaP_esales2000

            aaPanel_Kern
            Verify return code: 0 (ok)

            The sender email is config correctly and the SSL is also ( using Chain SSL ).

            Can I give you temporary access to the aaPanel?

              aaPanel_Kern
              Can you give me a hint on what to look? because it's happening only when I try to reject sending emails from the root.

              That is the error that I'm receiving

              Versions:
              WordPress: 6.0.3
              WordPress MS: No
              PHP: 7.4.33
              WP Mail SMTP: 3.8.0

              Params:
              Mailer: smtp
              Constants: Yes
              ErrorInfo: SMTP Error: The following recipients failed: recipient@me.com: : Sender address rejected: Server configuration error
              Host: mail.mydomain.com
              Port: 465
              SMTPSecure: ssl
              SMTPAutoTLS: bool(true)
              SMTPAuth: bool(true)

              Server:
              OpenSSL: OpenSSL 1.0.2u 20 Dec 2019

              Debug:
              Email Source: WP Mail SMTP Pro
              Mailer: Other SMTP
              PHPMailer was able to connect to SMTP server but failed while trying to send an email.
              Email Source: WP Mail SMTP Pro
              Mailer: Other SMTP
              SMTP Error: The following recipients failed: recipient@me.com: : Sender address rejected: Server configuration error

              SMTP Debug:
              2023-05-08 05:33:55 Connection: opening to ssl://mail.mydomain.com:465, timeout=300, options=array()

              2023-05-08 05:33:55 Connection: opened

              2023-05-08 05:33:55 SERVER -> CLIENT: 220 mail.mydomain.com ESMTP Postfix (3.4.7)

              2023-05-08 05:33:55 CLIENT -> SERVER: EHLO tikair.co.il

              2023-05-08 05:33:55 SERVER -> CLIENT: 250-mail.mydomain.com250-PIPELINING250-SIZE 102400000250-VRFY250-ETRN250-AUTH PLAIN LOGIN250-ENHANCEDSTATUSCODES250-8BITMIME250-DSN250-SMTPUTF8250 CHUNKING

              2023-05-08 05:33:55 CLIENT -> SERVER: AUTH LOGIN

              2023-05-08 05:33:55 SERVER -> CLIENT: 334 VXNlcm5hbWU6

              2023-05-08 05:33:55 CLIENT -> SERVER: [credentials hidden]

              2023-05-08 05:33:55 SERVER -> CLIENT: 334 UGFzc3dvcmQ6

              2023-05-08 05:33:55 CLIENT -> SERVER: [credentials hidden]

              2023-05-08 05:33:55 SERVER -> CLIENT: 235 2.7.0 Authentication successful

              2023-05-08 05:33:55 CLIENT -> SERVER: MAIL FROM:noreply@mydomain.com

              2023-05-08 05:33:55 SERVER -> CLIENT: 250 2.1.0 Ok

              2023-05-08 05:33:55 CLIENT -> SERVER: RCPT TO:recipient@me.com

              2023-05-08 05:33:55 SERVER -> CLIENT: 451 4.3.5 noreply@mydomain.com: Sender address rejected: Server configuration error

              2023-05-08 05:33:55 SMTP ERROR: RCPT TO command failed: 451 4.3.5 noreply@mydomain.com: Sender address rejected: Server configuration error

              2023-05-08 05:33:55 CLIENT -> SERVER: QUIT

              2023-05-08 05:33:55 SERVER -> CLIENT: 221 2.0.0 Bye

              2023-05-08 05:33:55 Connection: closed

              SMTP Error: The following recipients failed: recipient@me.com: noreply@mydomain.com: Sender address rejected: Server configuration error

              That my mail config

              readme_directory = /usr/share/doc/postfix3-3.4.7/README_FILES
              meta_directory = /etc/postfix
              shlib_directory = /usr/lib/postfix
              virtual_mailbox_domains = sqlite:/etc/postfix/sqlite_virtual_domains_maps.cf
              virtual_alias_maps = sqlite:/etc/postfix/sqlite_virtual_alias_maps.cf, sqlite:/etc/postfix/sqlite_virtual_alias_domain_maps.cf, sqlite:/etc/postfix/sqlite_virtual_alias_domain_catchall_maps.cf
              virtual_mailbox_maps = sqlite:/etc/postfix/sqlite_virtual_mailbox_maps.cf, sqlite:/etc/postfix/sqlite_virtual_alias_domain_mailbox_maps.cf
              smtpd_sasl_type = dovecot
              smtpd_sasl_path = private/auth
              smtpd_sasl_auth_enable = yes
              smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination
              smtpd_use_tls = yes
              smtp_tls_security_level = may
              smtpd_tls_security_level = may
              virtual_transport = lmtp:unix:private/dovecot-lmtp
              message_size_limit = 102400000
              smtpd_milters = inet:127.0.0.1:11332
              non_smtpd_milters = inet:127.0.0.1:11332
              milter_protocol = 6
              milter_default_action = accept
              default_process_limit = 100
              smtpd_client_connection_count_limit = 10
              smtpd_client_connection_rate_limit = 30
              queue_minfree = 20971520
              header_size_limit = 51200
              smtpd_recipient_limit = 400
              #smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access

              smtpd_tls_chain_files = /www/server/panel/plugin/mail_sys/cert/mydomain.com/privkey.pem,/www/server/panel/plugin/mail_sys/cert/mydomain.com/fullchain.pem
              tls_server_sni_maps = hash:/etc/postfix/vmail_ssl.map

              milter_mail_macros = i {mail_addr} {client_addr} {client_name} {auth_authen}

                aaP_esales2000
                Hello, is it normal for Send mail to use the relevant user to send mail in the mail server?
                Is it normal to add a # comment to the configuration of milter_mail_macros and restart postfix?

                  Hello, can you give us your aapanel information? The server first makes a snapshot backup, if possible, please send it to kern@aapanel.com.
                  It is recommended to fill in the following content
                  Post link:
                  SSH IP address, account password and port:
                  aapanel login link address and account password:
                  Website background login information:
                  Email account information:

                  If there is no post link, it will not be possible to know which user's information it is, and the problem will not be processed

                  aaP_esales2000

                    aaPanel_Kern
                    Its because
                    smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access
                    is comment.
                    If you will uncomment smtp_sender_restrictions.. you will receive an error