alpine: Insecure connection after a /tls is sent (CVE-2020-14929)
Alpine before 2.23 silently proceeds to use an insecure connection after a /tls is sent in certain circumstances involving PREAUTH, which is a less secure behavior than the alternative of closing the connection and letting the user decide what they would like to do.
References:
- http://mailman13.u.washington.edu/pipermail/alpine-info/2020-June/008989.html
- https://nvd.nist.gov/vuln/detail/CVE-2020-14929