A dpkg security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, 21.10, and 22.04 LTS.

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Ubuntu Security Notice USN-5446-1
May 26, 2022

dpkg vulnerability
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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:

A malicious source package could write files outside the unpack directory.

Software Description:
- dpkg: Debian package management system

Details:

Max Justicz discovered that dpkg incorrectly handled unpacking certain
source packages. If a user or an automated system were tricked into
unpacking a specially crafted source package, a remote attacker could
modify files outside the target unpack directory, leading to a denial of
service or potentially gaining access to the system.

Update instructions:

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

Ubuntu 22.04 LTS:
dpkg 1.21.1ubuntu2.1
libdpkg-perl 1.21.1ubuntu2.1

Ubuntu 21.10:
dpkg 1.20.9ubuntu2.2
libdpkg-perl 1.20.9ubuntu2.2

Ubuntu 20.04 LTS:
dpkg 1.19.7ubuntu3.2
libdpkg-perl 1.19.7ubuntu3.2

Ubuntu 18.04 LTS:
dpkg 1.19.0.5ubuntu2.4
libdpkg-perl 1.19.0.5ubuntu2.4

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

References:
  https://ubuntu.com/security/notices/USN-5446-1
CVE-2022-1664

Package Information:
  https://launchpad.net/ubuntu/+source/dpkg/1.21.1ubuntu2.1
  https://launchpad.net/ubuntu/+source/dpkg/1.20.9ubuntu2.2
  https://launchpad.net/ubuntu/+source/dpkg/1.19.7ubuntu3.2
  https://launchpad.net/ubuntu/+source/dpkg/1.19.0.5ubuntu2.4