http.cc in Squid 3.x before 3.5.15 and 4.x before 4.0.7 proceeds with the storage of certain data after a response-parsing failure, which allows remote HTTP servers to cause a denial of service (assertion failure and daemon exit) via a malformed response. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-2571
