Updated php packages that fix various security issues are now available.
PHP is an HTML-embedded scripting language commonly used with the Apache HTTP server. Stefan Esser discovered a flaw when memory_limit configuration setting is enabled in versions of PHP 4 before 4.3.8. If a remote attacker could force the PHP interpreter to allocate more memory than the memory_limit setting before script execution begins, then the attacker may be able to supply the contents of a PHP hash table remotely. This hash table could then be used to execute arbitrary code as the 'apache' user. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-0594 to this issue. This issue may be exploitable if using the default PHP configuration with the "register_globals" setting of "On". The Apache memory exhaustion bug, fixed in a previous update to CentOS Linux 3, may also allow this PHP issue to be exploited; this Apache bug does not affect CentOS Enterprise Linux 2.1. Stefan Esser discovered a flaw in the strip_tags function in versions of PHP before 4.3.8. The strip_tags function is commonly used by PHP scripts to prevent Cross-Site-Scripting attacks by removing HTML tags from user-supplied form data. By embedding NUL bytes into form data, HTML tags can in some cases be passed intact through the strip_tags function, which may allow a Cross-Site-Scripting attack. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-0595 to this issue. All users of PHP are advised to upgrade to these updated packages, which contain backported patches that address these issues.