Zoho ManageEngine ServiceDesk Plus before 11306, ServiceDesk Plus MSP before 10530, and SupportCenter Plus before 11014 are vulnerable to unauthenticated remote code execution. This is related to /RestAPI URLs in a servlet, and ImportTechnicians in the Struts configuration.
https://www.cisa.gov/news-events/cybersecurity-advisories/aa21-336a
https://www.tenable.com/cyber-exposure/tenable-2022-threat-landscape-report
https://www.tenable.com/blog/cve-2021-44515-zoho-patches-manageengine-zero-day-exploited-in-the-wild
http://packetstormsecurity.com/files/165400/ManageEngine-ServiceDesk-Plus-Remote-Code-Execution.html