A PackageKit security update has been released for Ubuntu Linux 16.04 LTS, 18.04 LTS, and 20.04 LTS.

USN-4538-1: PackageKit vulnerabilities

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Ubuntu Security Notice USN-4538-1
September 24, 2020

packagekit vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in PackageKit.

Software Description:
- packagekit: Provides a package management service

Details:

Vaisha Bernard discovered that PackageKit incorrectly handled certain
methods. A local attacker could use this issue to learn the MIME type of
any file on the system. (CVE-2020-16121)

Sami Niemimäki discovered that PackageKit incorrectly handled local deb
packages. A local user could possibly use this issue to install untrusted
packages, contrary to expectations. (CVE-2020-16122)

Update instructions:

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

Ubuntu 20.04 LTS:
packagekit 1.1.13-2ubuntu1.1

Ubuntu 18.04 LTS:
packagekit 1.1.9-1ubuntu2.18.04.6

Ubuntu 16.04 LTS:
packagekit 0.8.17-4ubuntu6~gcc5.4ubuntu1.5

After a standard system update you need to reboot your computer to make all
the necessary changes.

References:
  https://usn.ubuntu.com/4538-1
CVE-2020-16121, CVE-2020-16122

Package Information:
  https://launchpad.net/ubuntu/+source/packagekit/1.1.13-2ubuntu1.1
  https://launchpad.net/ubuntu/+source/packagekit/1.1.9-1ubuntu2.18.04.6
  https://launchpad.net/ubuntu/+source/packagekit/0.8.17-4ubuntu6~gcc5.4ubuntu1.5