goform/Docsis_system on Cisco EPC3928 devices allows remote attackers to cause a denial of service (device crash) via a long LanguageSelect parameter, related to a "Gateway HTTP Corruption Denial of Service" issue, aka Bug ID CSCuy28100.
https://www.exploit-db.com/exploits/39904/
http://www.securityfocus.com/bid/91543
http://www.securityfocus.com/archive/1/538627/100/0/threaded