CGA-qp3h-4h2p-2756

This vulnerability requires upgrading from Quarkus 2.13.8.Final to 3.24.0. This major version upgrade involves significant breaking changes including:

• Migration from javax.* to jakarta.* packages (Jakarta EE 10)
• Hibernate ORM 5.6 to 6.2 with API and behavior changes
• Complete rewrite of OpenTelemetry integration
• Changed CDI behavior and testing annotations

Keycloak 21.1.2 is the last release in the 21.x series and is tightly coupled to Quarkus 2.x. The upgrade would require extensive code changes throughout Keycloak. Upstream maintainers would need to implement the required changes to support Quarkus 3.x in the 21.x version stream.