PHP is a general-purpose scripting language widely used to develop web-based applications. It can run inside a web server using the mod_php module or the CGI version and also stand-alone in a CLI.
Multiple vulnerabilities have been found and fixed in PHP:
Attackers could leverage these issues to exploit applications that are assumed to be secure through the use of proper register_globals, safe_mode or open_basedir parameters. Remote attackers could also conduct cross-site scripting attacks if a page calling phpinfo() was available. Finally, a local attacker could cause a local Denial of Service using malicious session.save_path options.
There is no known workaround that would solve all issues at this time.
All PHP users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose dev-php/php
All mod_php users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose dev-php/mod_php
All php-cgi users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose dev-php/php-cgi