mail/dovecot -- multiple vulnerabilities

Aki Tuomi reports:

Parsing mails with a large number of MIME parts could have resulted in excessive CPU usage or a crash due to running out of stack memory..

[source]

Dovecot's NTLM implementation does not correctly check message buffer size, which leads to reading past allocation which can lead to crash

[source]

lmtp/submission: Issuing the RCPT command with an address that has the empty quoted string as local-part causes the lmtp service to crash.

[source]

Dovecot's RPA mechanism implementation accepts zero-length message, which leads to assert-crash later on.

[source]