Dovecot -- Multiple vulnerabilities

Aki Tuomi reports:

Submission-login crashes with signal 11 due to null pointer access when authentication is aborted by disconnecting. This can lead to denial-of-service attack by persistent attacker(s).

Aki Tuomi reports:

Submission-login crashes when authentication is started over TLS secured channel and invalid authentication message is sent. This can lead to denial-of-service attack by persistent attacker(s).