The mb_parse_str function in PHP 4.0.0 through 4.4.6 and 5.0.0 through 5.2.1 sets the internal register_globals flag and does not disable it in certain cases when a script terminates, which allows remote attackers to invoke available PHP scripts with register_globals functionality that is not detectable by these scripts, as demonstrated by forcing a memory_limit violation.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10245
https://issues.rpath.com/browse/RPL-1268
http://www.vupen.com/english/advisories/2007/2732
http://www.ubuntu.com/usn/usn-455-1
http://www.securityfocus.com/bid/25159
http://www.securityfocus.com/bid/23016
http://www.securityfocus.com/archive/1/466166/100/0/threaded
http://www.redhat.com/support/errata/RHSA-2007-0162.html
http://www.redhat.com/support/errata/RHSA-2007-0153.html
http://www.php-security.org/MOPB/MOPB-26-2007.html
http://www.novell.com/linux/security/advisories/2007_32_php.html
http://www.mandriva.com/security/advisories?name=MDKSA-2007:090
http://www.mandriva.com/security/advisories?name=MDKSA-2007:089
http://www.mandriva.com/security/advisories?name=MDKSA-2007:088
http://www.debian.org/security/2007/dsa-1283
http://us2.php.net/releases/5_2_2.php
http://us2.php.net/releases/4_4_7.php
http://security.gentoo.org/glsa/glsa-200705-19.xml
http://secunia.com/advisories/26235
http://secunia.com/advisories/25445
http://secunia.com/advisories/25062
http://secunia.com/advisories/25057
http://secunia.com/advisories/25056
http://secunia.com/advisories/24965
http://secunia.com/advisories/24945
http://secunia.com/advisories/24924
http://secunia.com/advisories/24909
http://rhn.redhat.com/errata/RHSA-2007-0155.html
http://lists.apple.com/archives/security-announce//2007/Jul/msg00004.html