logstash -- Remote command execution in Logstash zabbix and nagios_nsca outputs

Elastic reports:

The vulnerability impacts deployments that use the either the
zabbix or the nagios_nsca outputs. In these cases, an attacker
with an ability to send crafted events to any source of data for
Logstash could execute operating system commands with the
permissions of the Logstash process.
Deployments that do not use the zabbix or the nagios_nsca outputs
are not vulnerable and do not need to upgrade for this reason.
We have added this vulnerability to our CVE page and are working
on filling out the CVE.
We would like to thank Jan Karwowski and Danila Borisiuk for
reporting the issue and working with us on the resolution.