Buffer overflow in the gopherToHTML function in gopher.cc in the Gopher reply parser in Squid 3.0 before 3.0.STABLE26, 3.1 before 3.1.15, and 3.2 before 3.2.0.11 allows remote Gopher servers to cause a denial of service (memory corruption and daemon restart) or possibly have unspecified other impact via a long line in a response. NOTE: This issue exists because of a CVE-2005-0094 regression.

dns_internal.cc in Squid 3.1.6, when IPv6 DNS resolution is not enabled, accesses an invalid socket during an IPv4 TCP DNS query, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via vectors that trigger an IPv4 DNS response with the TC bit set.

The string-comparison functions in String.cci in Squid 3.x before 3.1.8 and 3.2.x before 3.2.0.2 allow remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted request.

lib/rfc1035.c in Squid 2.x, 3.0 through 3.0.STABLE22, and 3.1 through 3.1.0.15 allows remote attackers to cause a denial of service (assertion failure) via a crafted DNS packet that only contains a header.

Squid 3.0 through 3.0.STABLE16 and 3.1 through 3.1.0.11 allows remote attackers to cause a denial of service via malformed requests including (1) "missing or mismatched protocol identifier," (2) missing or negative status value," (3) "missing version," or (4) "missing or invalid status number," related to (a) HttpMsg.cc and (b) HttpReply.cc.

Squid 3.0 through 3.0.STABLE16 and 3.1 through 3.1.0.11 does not properly enforce "buffer limits and related bound checks," which allows remote attackers to cause a denial of service via (1) an incomplete request or (2) a request with a large header size, related to (a) HttpMsg.cc and (b) client_side.cc.

Squid 2.7 to 2.7.STABLE5, 3.0 to 3.0.STABLE12, and 3.1 to 3.1.0.4 allows remote attackers to cause a denial of service via an HTTP request with an invalid version number, which triggers a reachable assertion in (1) HttpMsg.c and (2) HttpStatusLine.c.

Squid before 2.3STABLE5 in HTTP accelerator mode does not enable access control lists (ACLs) when the httpd_accel_host and http_accel_with_proxy off settings are used, which allows attackers to bypass the ACLs and conduct unauthorized activities such as port scanning.