On the main PHP.net site there's an announcement about the release of the latest version in the PHP 5.6.x series - PHP 5.6.29:

The PHP development team announces the immediate availability of PHP 5.6.29. This is a security release. Several security bugs were fixed in this release. All PHP 5.6 users are encouraged to upgrade to this version.

Bugs fixed in this version include changes in the Opcache, OpenSSL, SOAP, SQLite3 Standard libraries. You can view the full list of changes in the Changelog and get the downloads from the usual place: the downloads page for the source packages and windows.php.net for the Windows binary downloads.