Apache Struts 2.x before 2.3.25 does not sanitize text in the Locale object constructed by I18NInterceptor, which might allow remote attackers to conduct cross-site scripting (XSS) attacks via unspecified vectors involving language display.
https://github.com/advisories/GHSA-2j4q-9fff-236j
http://www.securitytracker.com/id/1035272