The PHP.net site has announced both the release of PHP 5.3.29 and a reminder that the PHP 5.3.x series is coming close to its "end of life" date.
The PHP development team announces the immediate availability of PHP 5.3.29. This release marks the end of life of the PHP 5.3 series. Future releases of this series are not planned. All PHP 5.3 users are encouraged to upgrade to the current stable version of PHP 5.5 or previous stable version of PHP 5.4, which are supported till at least 2016 and 2015 respectively. PHP 5.3.29 contains about 25 potentially security related fixes backported from PHP 5.4 and 5.5
If you're using any release in the PHP 5.3.x series, it's highly recommended you either update to this latest version or you make the jump up to something in the PHP 5.4 or 5.5 series. You can get this latest release either from the main downloads page or for Windows users the windows.php.net site. The full change log can be found here.