The htcpHandleTstRequest function in htcp.c in Squid 2.x before 2.6.STABLE24 and 2.7 before 2.7.STABLE8, and htcp.cc in 3.0 before 3.0.STABLE24, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via crafted packets to the HTCP port.
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.
Last updated 25 August 2025
Last updated 25 August 2025
Last updated 25 August 2025
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.
A denial of service flaw was found in the way Squid proxy caching server internally processed NULL buffers. A remote, trusted client could use this flaw to cause squid daemon crash (dereference NULL pointer) when processing specially-crafted request.
References: [1] http://www.squid-cache.org/Advisories/SQUID-20103.txt
Upstream patch (against Squid v3.0): [2] http://www.squid-cache.org/Versions/v3/3.0/changesets/squid-3.0-9189.patch
Upstream patch (against Squid v3.1): [3] http://www.squid-cache.org/Versions/v3/3.1/changesets/squid-3.1-10090.patch
Credit: The vulnerability was discovered by Phil Oester.