Heap-based buffer overflow in the Icmp6::Recv function in icmp/Icmp6.cc in the pinger utility 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.
Squid before 3.5.6 does not properly handle CONNECT method peer responses when configured with cache_peer, which allows remote attackers to bypass intended restrictions and gain access to a backend proxy via a CONNECT request.
CRLF injection vulnerability in Squid before 3.1.1 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a crafted header in a response.
Off-by-one error in the snmpHandleUdp function in snmp_core.cc in Squid 2.x and 3.x, when an SNMP port is configured, allows remote attackers to cause a denial of service (crash) or possibly execute arbitrary code via a crafted UDP SNMP request, which triggers a heap-based buffer overflow.
The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.