The parse_str function in (1) PHP, (2) Hardened-PHP, and (3) Suhosin, when called without a second parameter, might allow remote attackers to overwrite arbitrary variables by specifying variable names and values in the string to be parsed. NOTE: it is not clear whether this is a design limitation of the function or a bug in PHP, although it is likely to be regarded as a bug in Hardened-PHP and Suhosin.
https://exchange.xforce.ibmcloud.com/vulnerabilities/34836
http://www.securityfocus.com/archive/1/471275/100/0/threaded
http://www.securityfocus.com/archive/1/471204/100/0/threaded
http://www.securityfocus.com/archive/1/471178/100/0/threaded
http://www.acid-root.new.fr/advisories/14070612.txt