OpenSMTPd -- LPE and RCE in OpenSMTPD's default install

OpenSMTPD developers reports:

An out of bounds read in smtpd allows an attacker to inject arbitrary commands into the envelope file which are then executed as root. Separately, missing privilege revocation in smtpctl allows arbitrary commands to be run with the _smtpq group.

An unprivileged local attacker can read the first line of an arbitrary file (for example, root's password hash in /etc/master.passwd) or the entire contents of another user's file (if this file and /var/spool/smtpd/ are on the same filesystem).

[source]