=========================================================================Ubuntu Security Notice USN-5078-2
September 15, 2021

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

- Ubuntu 16.04 ESM

Summary:

Squashfs-Tools could be made to overwrite files.

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

Details:

USN-5078-1 fixed several vulnerabilities in Squashfs-Tools.
This update provides the corresponding update for Ubuntu 16.04 ESM.

Original advisory details:

 Etienne Stalmans discovered that Squashfs-Tools mishandled certain
 malformed SQUASHFS files. An attacker could use this vulnerability
 to write arbitrary files to the filesystem. (CVE-2021-40153)

 Richard Weinberger discovered that Squashfs-Tools mishandled certain
 malformed SQUASHFS files. An attacker could use this vulnerability to
 write arbitrary files to the filesystem. (CVE-2021-41072)

Update instructions:

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

Ubuntu 16.04 ESM:
  squashfs-tools                  1:4.3-3ubuntu2.16.04.3+esm1

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

References:
  https://ubuntu.com/security/notices/USN-5078-2
  https://ubuntu.com/security/notices/USN-5078-1
  CVE-2021-40153, CVE-2021-41072