The Jakarta Multipart parser in Apache Struts 2 2.3.x before 2.3.32 and 2.5.x before 2.5.10.1 has incorrect exception handling and error-message generation during file-upload attempts, which allows remote attackers to execute arbitrary commands via a crafted Content-Type, Content-Disposition, or Content-Length HTTP header, as exploited in the wild in March 2017 with a Content-Type header containing a #cmd= string.
https://securityaffairs.com/155935/malware/nkabuse-abuses-nkn-technology.html
https://www.secureworks.com/research/gold-melody-profile-of-an-initial-access-broker?&web_view=true
https://www.symantec.com/security-center/network-protection-security-advisories/SA145
https://www.kb.cert.org/vuls/id/834067
https://www.exploit-db.com/exploits/41614/
https://twitter.com/theog150/status/841146956135124993
https://support.lenovo.com/us/en/product_security/len-14200
https://struts.apache.org/docs/s2-046.html
https://struts.apache.org/docs/s2-045.html
https://security.netapp.com/advisory/ntap-20170310-0001/
https://nmap.org/nsedoc/scripts/http-vuln-cve2017-5638.html
https://isc.sans.edu/diary/22169
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03723en_us
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbgn03749en_us
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbgn03733en_us
https://cwiki.apache.org/confluence/display/WW/S2-046
https://cwiki.apache.org/confluence/display/WW/S2-045
http://www.securitytracker.com/id/1037973
http://www.securityfocus.com/bid/96729
http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
http://www.eweek.com/security/apache-struts-vulnerability-under-attack.html
http://www.arubanetworks.com/assets/alert/ARUBA-PSA-2017-002.txt
http://blog.talosintelligence.com/2017/03/apache-0-day-exploited.html