Apache Struts 2.0.0 through 2.3.15 allows remote attackers to execute arbitrary OGNL expressions via a parameter with a crafted (1) action:, (2) redirect:, or (3) redirectAction: prefix.
https://exchange.xforce.ibmcloud.com/vulnerabilities/90392
http://www.oracle.com/technetwork/topics/security/cpujul2015-2367936.html
http://www.oracle.com/technetwork/topics/security/cpujan2014-1972949.html
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20131023-struts2
https://github.com/nth347/CVE-2013-2251
https://github.com/advisories/GHSA-47qp-8v9g-39hp
https://github.com/yafeile/CVE
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2013-2251
http://www.securitytracker.com/id/1032916
http://www.securitytracker.com/id/1029184
http://www.securityfocus.com/bid/64758
http://www.securityfocus.com/bid/61189
http://struts.apache.org/release/2.3.x/docs/s2-016.html
http://seclists.org/fulldisclosure/2013/Oct/96
http://packetstormsecurity.com/files/159629/Apache-Struts-2-Remote-Code-Execution.html