webinc/bxe/scripts/loadsave.php in Flux CMS 1.5.0 and earlier allows remote attackers to execute arbitrary code by overwriting a PHP file in webinc/bxe/scripts/ via a filename in the XML parameter and PHP sequences in the request body, then making a direct request for this filename.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.