Problem

Jira Data Center customers are unable to prevent email impersonation or email spoofing for incoming emails using standard Jira functionality. 

Suggested Solutions 

Implement DMARC functionality for incoming emails similar to the Jira Cloud implementation. Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a standard email authentication method that helps protect email senders and recipients from fraudulent emails or spoofing and phishing attacks.

Current Workarounds

Enable email filtering/spam protection on the mail server.