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Issue Unencrypted Connections SMTP Auth on Port 25

hschramm

Basic Pleskian
Hi there,

with a fresh and clean plesk obsidian install it is possible to send e-mails as a client unencrypted. The AuthData it self is encrypted by DIGEST-MD5 but not the connection itself.
There is a deprecated option called smtpd_tls_auth_only. This option is now smtpd_enforce_tls = enforce but against RFC 2487. Disabling the auth on port 25 via plesk is not possible. So how do I prevent unencrypted connections from clients to port 25.

Kind regards,
Holger
 
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