The PHP.net site has announced the release of the latest versions of the current releases of the PHP language: PHP versions 5.6.12, 5.4.44 and 5.5.28.
The PHP development team announces the immediate availability of PHP [versions 5.6.12, 5.4.44 and 5.5.28]. 12 security-related issues were fixed in this release. All PHP 5.6 users are encouraged to upgrade to this version.
It's also pointed out that this 5.5.x release marks the first security-only bugfix release according to their release calendar. As always, you can get these latest versions from the downloads page or the windows.php.net site for the Windows binaries. You can view the full list of changes in these releases in the Changelog for each version.