Apache Struts is the United States Apache (Apache) Foundation, an open source project , is a set of open source MVC framework for creating enterprise-class Java Web applications , mainly provides two versions of the framework products , Struts 1 and Struts 2. Apache Struts denial of service vulnerability , the vulnerability is caused by a flaw in the processing of Multipart requests containing non-file format fields . An attacker could exploit this vulnerability to cause a denial of service.