The Image Manager in MOStlyCE before 2.4, as used in Mambo 4.6.3 and earlier, allows remote attackers to rename arbitrary files and cause a denial of service via modified file[NewFile][name], file[NewFile][tmp_name], and file[NewFile][size] parameters in a FileUpload command, which are used to modify equivalent variables in $_FILES that are accessed when the is_uploaded_file check fails.
https://exchange.xforce.ibmcloud.com/vulnerabilities/39986
http://www.vupen.com/english/advisories/2008/0325
http://www.securityfocus.com/bid/27472
http://www.securityfocus.com/archive/1/487128/100/200/threaded
http://secunia.com/advisories/28670
http://forum.mambo-foundation.org/showthread.php?t=10158
http://archives.neohapsis.com/archives/bugtraq/2008-02/0444.html