Unrestricted file upload vulnerability in the Settings_Vtiger_CompanyDetailsSave_Action class in modules/Settings/Vtiger/actions/CompanyDetailsSave.php in Vtiger CRM 6.4.0 allows remote authenticated users to execute arbitrary code by uploading a crafted image file with an executable extension, then accessing it via a direct request to the file in test/logo/.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-6000.