Code injection exists in Kernel/System/Spelling.pm in Open Ticket Request System (OTRS) 5 before 5.0.24, 4 before 4.0.26, and 3.3 before 3.3.20. In the agent interface, an authenticated remote attacker can execute shell commands as the webserver user via URL manipulation.
https://www.otrs.com/security-advisory-2017-07-security-update-otrs-framework/
https://www.debian.org/security/2017/dsa-4047
https://lists.debian.org/debian-lts-announce/2017/12/msg00015.html