If you are using Atlassian Crowd and Crowd Data Center, it is better to check your system if any vulnerability exists.
It is a software application that gathers your organization's applications and enables access from one location. It provide easy management of users and softwares.
Due to incorrect configuration of pdkinstall development plugin, attackers can install arbitrary plugins and gain ability of remote code execution.
Update your Atlassian Crowd and Crowd Data Center to the latest version.