WordPress 4.4.1 is now available. This is a security release for all previous versions and we strongly encourage you to update your sites immediately.
WordPress versions 4.4 and earlier are affected by a cross-site scripting vulnerability that could allow a site to be compromised. This was reported by Crtc4L.
There were also several non-security bug fixes:

• Emoji support has been updated to include all of the latest emoji characters, including the new diverse emoji!