This version is a security patch release for all previous versions. It patches a potential cross site scripting vulnerability that could be used by users with a contributor or higher role (so only when you have non-administrator users who have a role capability that allows them to create posts).
I’m not going to detail how it could be used, but this can only be exploited by a user who has a role allowing them to create posts. Additionally, the necessary parameters for exploiting it is in a feature that is not published in the documentation, so it is not anything obvious.