A cross platform, powerful and entirely free server-side scripting language. Supports many databases (ODBC, as well as many native interfaces such as MySQL and MS-SQL) as well as many APIs and protocols (LDAP, IMAP, COM, Java, SNMP, arbitary precision math, GD, zlib and more). Supports ISAPI (IIS) and ApacheNT under Windows, as well as Apache and other servers under UNIX.
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PHP is a reflective computer programming language originally designed for producing dynamic web pages.PHP is used mainly in server-side scripting, but can be used from a command line interface or in standalone graphical applications. Textual User Interfaces can also be created using ncurses. PHP is a recursive initialism for PHP: Hypertext Preprocessor.
The PHP development team would like to announce the immediate availability of PHP 5.4.3 and PHP 5.3.13. All users are encouraged to upgrade to PHP 5.4.3 or PHP 5.3.13
The releases complete a fix for a vulnerability in CGI-based setups (CVE-2012-2311). Note: mod_php and php-fpm are not vulnerable to this attack.
PHP 5.4.3 fixes a buffer overflow vulnerability in the apache_request_headers() (CVE-2012-2329). The PHP 5.3 series is not vulnerable to this issue.