An issue was discovered in AppArmor before 2.12. Incorrect handling of unknown AppArmor profiles in AppArmor init scripts, upstart jobs, and/or systemd unit files allows an attacker to possibly have increased attack surfaces of processes that were intended to be confined by AppArmor. This is due to the common logic to handle 'restart' operations removing AppArmor profiles that aren't found in the typical filesystem locations, such as /etc/apparmor.d/. Userspace projects that manage their own AppArmor profiles in atypical directories, such as what's done by LXD and Docker, are affected by this flaw in the AppArmor init script logic.
If PAM is configured to read user-specified environment variables and UseLogin=yes in sshdconfig, then a hostile local user may attack /bin/login via LDPRELOAD or similar environment variables set via PAM.
Upstream fix:
https://anongit.mindrot.org/openssh.git/commit/?id=85bdcd7c92fe7ff133bbc4e10a65c91810f88755
Debian advisory:
https://www.debian.org/security/2016/dsa-3550