Apache Struts 2 2.3.20 through 2.3.28.1 allows remote attackers to bypass intended access restrictions and conduct redirection attacks by leveraging a default method.
https://struts.apache.org/docs/s2-040.html
https://bugzilla.redhat.com/show_bug.cgi?id=1348252
http://www.securityfocus.com/bid/91284
http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
http://www-01.ibm.com/support/docview.wss?uid=swg21987854
http://www-01.ibm.com/support/docview.wss?uid=ssg1S1009282