ObjectPlanet Opinio before 7.15 allows XXE attacks via three steps: modify a .css file to have <!ENTITY content, create a .xml file for a generic survey template (containing a link to this .css file), and import this .xml file at the survey/admin/folderSurvey.do?action=viewImportSurvey['importFile'] URI. The XXE can then be triggered at a admin/preview.do?action=previewSurvey&surveyId= URI.