A Squashfs-Tools security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, and 21.04.

USN-5078-1: Squashfs-Tools vulnerability

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Ubuntu Security Notice USN-5078-1
September 15, 2021

squashfs-tools vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.04
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Squashfs-Tools could be made to overwrite files.

Software Description:
- squashfs-tools: Tools to create and modify squashfs filesystems

Details:

Richard Weinberger discovered that Squashfs-Tools mishandled certain
malformed SQUASHFS files. An attacker could use this vulnerability to
write arbitrary files to the filesystem.

Update instructions:

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

Ubuntu 21.04:
squashfs-tools 1:4.4-2ubuntu0.2

Ubuntu 20.04 LTS:
squashfs-tools 1:4.4-1ubuntu0.2

Ubuntu 18.04 LTS:
squashfs-tools 1:4.3-6ubuntu0.18.04.4

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

References:
  https://ubuntu.com/security/notices/USN-5078-1
CVE-2021-41072

Package Information:
  https://launchpad.net/ubuntu/+source/squashfs-tools/1:4.4-2ubuntu0.2
  https://launchpad.net/ubuntu/+source/squashfs-tools/1:4.4-1ubuntu0.2
  https://launchpad.net/ubuntu/+source/squashfs-tools/1:4.3-6ubuntu0.18.04.4