Heap-based buffer overflow in the Icmp6::Recv function in icmp/Icmp6.cc in the pinger in Squid before 3.5.16 and 4.x before 4.0.8 allows remote servers to cause a denial of service (performance degradation or transition failures) or write sensitive information to log files via an ICMPv6 packet. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-3947