Re: [exim] CVE-2019-15846: Exim - local or remote attacker c…

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Author: Heiko Schlittermann
To: oss-security, Exim Users, Exim Announce
Subject: Re: [exim] CVE-2019-15846: Exim - local or remote attacker can execute programs with root privileges.
Heiko Schlittermann <hs@???> (Fr 06 Sep 2019 12:20:39 CEST):
> Mitigation
> ==========
> Do not offer TLS for incomming connections (tls_advertise_hosts).
> This mitigation is *not* recommended!

This should block the most popular attack vector:

In your MAIL ACL:

    deny    condition = ${if eq{\\}{${substr{-1}{1}{$tls_in_sni}}}}
            message = sorry

    Best regards from Dresden/Germany
    Viele Grüße aus Dresden
    Heiko Schlittermann
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