PHP is an HTML-embedded scripting language commonly used with the Apache HTTP Server. A flaw was found in the way PHP converted certain floating point values from string representation to a number. If a PHP script evaluated an attacker"s input in a numeric context, the PHP interpreter could cause high CPU usage until the script execution time limit is reached. This issue only affected i386 systems. A stack memory exhaustion flaw was found in the way the PHP filter_var function validated email addresses. An attacker could use this flaw to crash the PHP interpreter by providing excessively long input to be validated as an email address. A memory disclosure flaw was found in the PHP multi-byte string extension. If the mb_strcut function was called with a length argument exceeding the input string size, the function could disclose a portion of the PHP interpreter"s memory. All php53 users should upgrade to these updated packages, which contain backported patches to resolve these issues. After installing the updated packages, the httpd daemon must be restarted for the update to take effect.