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Vulnerability of Squid: assertion error via Large HTTP Response

Synthesis of the vulnerability 

An attacker can use an HTTP reply containing a large header, to force an assertion error in Squid, in order to trigger a denial of service.
Impacted software: Debian, openSUSE Leap, RHEL, Squid, SUSE Linux Enterprise Desktop, SLES, Ubuntu.
Severity of this computer vulnerability: 2/4.
Number of vulnerabilities in this bulletin: 4.
Creation date: 24/02/2016.
Références of this announce: CVE-2016-2569, CVE-2016-2570, CVE-2016-2571, CVE-2016-2572, DSA-3522-1, openSUSE-SU-2016:2081-1, RHSA-2016:2600-02, SQUID-2016:2, SUSE-SU-2016:1996-1, SUSE-SU-2016:2089-1, USN-2921-1, USN-3557-1, VIGILANCE-VUL-19018.

Description of the vulnerability 

The Squid proxy analyzes HTTP replies from servers.

However, when a reply contains an HTTP header larger than 64k bytes, an assertion error occurs because developers did not except this case, which stops the process.

An attacker can therefore use an HTTP reply containing a large header, to force an assertion error in Squid, in order to trigger a denial of service.
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This threat announce impacts software or systems such as Debian, openSUSE Leap, RHEL, Squid, SUSE Linux Enterprise Desktop, SLES, Ubuntu.

Our Vigil@nce team determined that the severity of this cybersecurity alert is medium.

The trust level is of type confirmed by the editor, with an origin of internet server.

This bulletin is about 4 vulnerabilities.

A proof of concept or an attack tool is available, so your teams have to process this alert. An attacker with a technician ability can exploit this security alert.

Solutions for this threat 

Squid: version 3.5.15.
The version 3.5.15 is fixed:
  http://www.squid-cache.org/

Squid: patch for Large HTTP Response.
A patch is indicated in information sources.

Debian: new squid3 packages.
New packages are available:
  Debian 7: squid3 3.1.20-2.2+deb7u4
  Debian 8: squid3 3.4.8-6+deb8u2

openSUSE Leap 42.1: new squid packages.
New packages are available:
  openSUSE Leap 42.1: squid 3.3.14-6.1

RHEL 7: new squid packages.
New packages are available:
  RHEL 7: squid 3.5.20-2.el7

SUSE LE 11 SP4: new squid3 packages.
New packages are available:
  SUSE LE 11 SP4: squid3 3.1.23-8.16.27.1
  SUSE LE 11 SP4: squid3 3.1.23-8.16.30.1
  SUSE LE 11 SP4: squid3 3.1.23-8.16.27.1

Ubuntu: new squid3 packages (06/02/2018).
New packages are available:
  Ubuntu 17.10: squid3 3.5.23-5ubuntu1.1
  Ubuntu 16.04 LTS: squid3 3.5.12-1ubuntu7.5
  Ubuntu 14.04 LTS: squid3 3.3.8-1ubuntu6.11

Ubuntu: new squid3 packages (07/03/2016).
New packages are available:
  Ubuntu 15.10: squid3 3.3.8-1ubuntu16.2
  Ubuntu 14.04 LTS: squid3 3.3.8-1ubuntu6.6
  Ubuntu 12.04 LTS: squid3 3.1.19-1ubuntu3.12.04.6
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