Update dovecot to 2.2.34, and bump pigeonhole.
* CVE-2017-15130: TLS SNI config lookups may lead to excessive
memory usage, causing imap-login/pop3-login VSZ limit to be reached
and the process restarted. This happens only if Dovecot config has
local_name { } or local { } configuration blocks and attacker uses
randomly generated SNI servernames.
* CVE-2017-14461: Parsing invalid email addresses may cause a crash or
leak memory contents to attacker. For example, these memory contents
might contain parts of an email from another user if the same imap
process is reused for multiple users. First discovered by Aleksandar
Nikolic of Cisco Talos. Independently also discovered by "flxflndy"
via HackerOne.
* CVE-2017-15132: Aborted SASL authentication leaks memory in login
process.
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