I'm a member of the Hibernate Team at Red Hat.
The first bug-fix release for Hibernate ORM 5.2 has just been published. It is tagged at https://github.com/hibernate/hibernate-orm/releases/tag/5.2.1
The complete list of changes can be found here.
For information on consuming the release via your favorite dependency-management-capable build tool, see http://hibernate.org/orm/downloads/