=========================================================================Ubuntu Security Notice USN-5491-1
June 22, 2022

squid, squid3 vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 22.04 LTS
- Ubuntu 21.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Squid could be made to crash if it received specially crafted network
traffic.

Software Description:
- squid: Web proxy cache server
- squid3: Web proxy cache server

Details:

Joshua Rogers discovered that Squid incorrectly handled the Gopher
protocol. A remote attacker could possibly use this issue to cause Squid to
crash, resulting in a denial of service.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 22.04 LTS:
  squid                           5.2-1ubuntu4.1

Ubuntu 21.10:
  squid                           4.13-10ubuntu5.1

Ubuntu 20.04 LTS:
  squid                           4.10-1ubuntu1.6

Ubuntu 18.04 LTS:
  squid                           3.5.27-1ubuntu1.13

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5491-1
  CVE-2021-46784

Package Information:
  https://launchpad.net/ubuntu/+source/squid/5.2-1ubuntu4.1
  https://launchpad.net/ubuntu/+source/squid/4.13-10ubuntu5.1
  https://launchpad.net/ubuntu/+source/squid/4.10-1ubuntu1.6
  https://launchpad.net/ubuntu/+source/squid3/3.5.27-1ubuntu1.13