Squid 3.x before 3.5.16 and 4.x before 4.0.8 improperly perform bounds checking, which allows remote attackers to cause a denial of service via a crafted HTTP response, related to Vary headers.
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.
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.
The Edge Side Includes (ESI) parser in Squid 3.x before 3.5.15 and 4.x before 4.0.7 does not check buffer limits during XML parsing, which allows remote HTTP servers to cause a denial of service (assertion failure and daemon exit) via a crafted XML document, related to esi/CustomParser.cc and esi/CustomParser.h.
Squid 3.x before 3.5.15 and 4.x before 4.0.7 does not properly append data to String objects, which allows remote servers to cause a denial of service (assertion failure and daemon exit) via a long string, as demonstrated by a crafted HTTP Vary header.
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.
Multiple memory leaks in tools/cachemgr.cc in cachemgr.cgi in Squid 2.x and 3.x before 3.1.22, 3.2.x before 3.2.4, and 3.3.x before 3.3.0.2 allow remote attackers to cause a denial of service (memory consumption) via (1) invalid Content-Length headers, (2) long POST requests, or (3) crafted authentication credentials.
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.