CVE-2016-4553: High severity ubuntu vulnerability
clientside.cc in Squid before 3.5.18 and 4.x before 4.0.10 does not properly ignore the Host header when absolute-URI is provided, which allows remote attackers to conduct cache-poisoning attacks via an HTTP request.
Other sources
Due to incorrect data validation of intercepted HTTP Request messages Squid is vulnerable to clients bypassing the protection against CVE-2009-0801 related issues. This leads to cache poisoning.
External references:
http://www.squid-cache.org/Advisories/SQUID-20167.txt
Upstream fix:
http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-14039.patch
— Red Hat
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2016-4553?
CVE-2016-4553 has a critical severity level as it allows remote attackers to conduct cache-poisoning attacks by exploiting improper handling of the Host header.
How do I fix CVE-2016-4553?
To fix CVE-2016-4553, upgrade Squid to version 3.5.18 or 4.0.10 or later.
Which versions of Squid are affected by CVE-2016-4553?
CVE-2016-4553 affects Squid versions prior to 3.5.18 and all versions in the 4.x series prior to 4.0.10.
What types of attacks can CVE-2016-4553 enable?
CVE-2016-4553 can enable cache-poisoning attacks, allowing attackers to serve malicious content to users.
Is CVE-2016-4553 relevant for all Squid deployments?
CVE-2016-4553 is particularly relevant for deployments using affected Squid versions that handle HTTP requests without proper validation.