Re: Insecure Mail Sending Warning

[Robert Pluim]

>>>>> On Fri, 23 Oct 2020 01:35:35 +0100, Robert Thorpe 
>>>>> <rt@robertthorpeconsulting.com> said:

    Robert> When I send mail I get a warning about security.
    >> The TLS connection to <mailserver> is insecure for the following reason:
    >> 
    >> * TLS1.0 protocol is deprecated by standard bodies.

    Robert> Where <mailserver> is the URL of my mailserver.

    Robert> Can I fix this or is the problem on my mail provider's side?

The problem is on the mail provider's side, I think.

Iʼm kind of surprised that a real mail provider still enables
TLS1.0. You can test what it supports using

gnutls-cli -p 587 <mailserver>

    Robert> I'm using port 587, which I thought was correct.

587 is the mail submission port. It normally starts out in cleartext,
and is then upgraded to TLS with a STARTTLS command. Iʼd recommend
465, which is TLS-only (although you'd have to set
smtpmail-stream-type to 'tls)

You'd still get the warning, but at least the entire connection would
be encrypted (not that that means much when using TLS1.0)

Robert
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