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Area

core

Describe the bug

Keycloak shouldn't reveal information about the local host name or IP in the emails message ID

Version

main

Regression

[ ] The issue is a regression

Expected behavior

The message ID should be derived from the email domain of the realm

Actual behavior

Date: Sat, 22 Mar 2025 20:29:14 +0000 (GMT)
From: Keycloak <[keycloak@example.com](mailto:keycloak@example.com)>
Reply-To: Keycloak <[keycloak@example.com](mailto:keycloak@example.com)>
To: [me@example.com](mailto:me@example.com)
Message-ID: <514684305.15.1742675354390@[192.168.1.78]>
Subject: [KEYCLOAK] - SMTP test message
MIME-Version: 1.0

How to Reproduce?

Send a test email from Keycloak

Anything else?

This has been discussed with the keycloak security mailing list to be a hardening issue. I'll prepare a PR