Your logs contain valid login and password. Also, note, that AUTH LOGIN (as well as AUTH PLAIN) is just base64, so password may be recovered in plain text.
# telnet mail.federcasapescara.it 25
Trying 185.4.142.93...
Connected to mail.federcasapescara.it.
Escape character is '^]'.
220 directadmin30.fastnom.com ESMTP Exim 4.94.2 Wed, 10 Nov 2021 12:17:45
+0100
EHLO test
250-directadmin30.fastnom.com Hello test [213.108.248.159]
250-SIZE 52428800
250-8BITMIME
250-PIPELINING
250-PIPE_CONNECT
250-AUTH PLAIN LOGIN
250-STARTTLS
250 HELP
AUTH LOGIN
334 VXNlcm5hbWU6
bmFzb25lQGZlZGVyY2FzYXBlc2NhcmEuaXQ=
334 UGFzc3dvcmQ6
Tmd1bGFtbWFtbXQxIQ==
235 Authentication succeeded
2021/11/10 11:20:15 Carlo via Exim-users <exim-users@???>:
> hi
> i'm playing with a nas i've installed debian stable on, and i used to
> have some scripts with mailx work to send me messages through external
> providers/servers/etc till i upgraded debian: now i can't send mails
> through mailx but i can through telnet and swaks: here are mailx and
> swaks logs, please treat me as a true noob
>
> echo “Subject: sendmail test” | mail -v troianicarlo@???
> LOG: MAIN
> <= nasone@??? U=root P=local S=479
> ➜ ~ delivering 1mk3js-0006Jf-IB
> R: smarthost for troianicarlo@???
> T: remote_smtp_smarthost for troianicarlo@???
> Connecting to mail.federcasapescara.it [185.4.142.93]:25 ... TFO mode
> sendto, no data: EINPROGRESS
> connected
> SMTP<< 220 directadmin30.fastnom.com ESMTP Exim 4.94.2 Mon, 08 Nov
> 2021 13:27:05 +0100
> SMTP>> EHLO ilmionasone.fritz.box
> SMTP<< 250-directadmin30.fastnom.com Hello
> host-95-247-26-164.retail.telecomitalia.it [95.247.26.164]
> 250-SIZE 52428800
> 250-8BITMIME
> 250-PIPELINING
> 250-PIPE_CONNECT
> 250-AUTH PLAIN LOGIN
> 250-STARTTLS
> 250 HELP
> SMTP>> STARTTLS
> SMTP<< 220 TLS go ahead
> SMTP(close)>>
> LOG: MAIN
> TLS session: (certificate verification failed): delivering
> unencrypted to H=mail.federcasapescara.it [185.4.142.93] (not in
> hosts_require_tls)
> Connecting to mail.federcasapescara.it [185.4.142.93]:25 ... TFO mode
> sendto, no data: EINPROGRESS
> connected
> SMTP<< 220 directadmin30.fastnom.com ESMTP Exim 4.94.2 Mon, 08 Nov
> 2021 13:27:05 +0100
> SMTP>> EHLO ilmionasone.fritz.box
> SMTP<< 250-directadmin30.fastnom.com Hello
> host-95-247-26-164.retail.telecomitalia.it [95.247.26.164]
> 250-SIZE 52428800
> 250-8BITMIME
> 250-PIPELINING
> 250-PIPE_CONNECT
> 250-AUTH PLAIN LOGIN
> 250-STARTTLS
> 250 HELP
> SMTP>> MAIL FROM:<nasone@???> SIZE=1515
> SMTP>> RCPT TO:<troianicarlo@???>
> SMTP>> DATA
> SMTP<< 250 OK
> SMTP<< 550 authentication required
> SMTP<< 503-All RCPT commands were rejected with this error:
> 503-authentication required
> 503 Valid RCPT command must precede DATA
> SMTP>> QUIT
> SMTP(close)>>
> LOG: MAIN
> ** troianicarlo@??? R=smarthost T=remote_smtp_smarthost
> H=mail.federcasapescara.it [185.4.142.93]: SMTP error from remote mail
> server after RCPT TO:<troianicarlo@???>: 550 authentication
> required
> LOG: MAIN
> <= <> R=1mk3js-0006Jf-IB U=Debian-exim P=local S=2021
> delivering 1mk3jv-0006Jl-Th
> R: system_aliases for nasone@???
> LOG: MAIN
> ** nasone@???: Unrouteable address
> LOG: MAIN
> Frozen (delivery error message)
> LOG: MAIN
> Completed
>
>
>
> swaks --tls --auth --to segreteria@??? --server
> mail.federcasapescara.it
> Username: nasone@???
> Password: xxx
> === Trying mail.federcasapescara.it:25...
> === Connected to mail.federcasapescara.it.
> <- 220 directadmin30.fastnom.com ESMTP Exim 4.94.2 Mon, 08 Nov 2021
> 22:22:41 +0100
> -> EHLO ilmionasone.fritz.box
> <- 250-directadmin30.fastnom.com Hello
> host-95-247-26-164.retail.telecomitalia.it [95.247.26.164]
> <- 250-SIZE 52428800
> <- 250-8BITMIME
> <- 250-PIPELINING
> <- 250-PIPE_CONNECT
> <- 250-AUTH PLAIN LOGIN
> <- 250-STARTTLS
> <- 250 HELP
> -> STARTTLS
> <- 220 TLS go ahead
> === TLS started with cipher TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128
> === TLS no local certificate set
> === TLS peer DN="/CN=directadmin30.fastnom.com"
> ~> EHLO ilmionasone.fritz.box
> <~ 250-directadmin30.fastnom.com Hello
> host-95-247-26-164.retail.telecomitalia.it [95.247.26.164]
> <~ 250-SIZE 52428800
> <~ 250-8BITMIME
> <~ 250-PIPELINING
> <~ 250-PIPE_CONNECT
> <~ 250-AUTH PLAIN LOGIN
> <~ 250 HELP
> ~> AUTH LOGIN
> <~ 334 VXNlcm5hbWU6
> ~> bmFzb25lQGZlZGVyY2FzYXBlc2NhcmEuaXQ=
> <~ 334 UGFzc3dvcmQ6
> ~> Tmd1bGFtbWFtbXQxIQ==
> <~ 235 Authentication succeeded
> ~> MAIL FROM:<root@???>
> <~ 250 OK
> ~> RCPT TO:<segreteria@???>
> <~ 250 Accepted
> ~> DATA
> <~ 354 Enter message, ending with "." on a line by itself
> ~> Date: Mon, 08 Nov 2021 22:21:39 +0100
> ~> To: segreteria@???
> ~> From: root@???
> ~> Subject: test Mon, 08 Nov 2021 22:21:39 +0100
> ~> Message-Id: <20211108222139.028193@???>
> ~> X-Mailer: swaks v20201014.0 jetmore.org/john/code/swaks/
> ~>
> ~> This is a test mailing
> ~>
> ~>
> ~> .
> <~ 250 OK id=1mkC6D-000Vj8-Sr
> ~> QUIT
> <~ 221 directadmin30.fastnom.com closing connection
> === Connection closed with remote host.
>
> --
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