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Ubuntu Security Notice USN-4721-1
February 04, 2021
flatpak vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
Summary:
Flatpak could be made to crash or run programs if it received
specially crafted input.
Software Description:
- flatpak: Application deployment framework for desktop apps
Details:
Simon McVittieg discovered that flatpak-portal service allowed sandboxed
applications to execute arbitrary code on the host system (a sandbox
escape). A malicious user could create a Flatpak application that set
environment variables, trusted by the Flatpak "run" command, and use it
to execute arbitrary code outside the sandbox.
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 20.10:
flatpak 1.8.2-1ubuntu0.1
libflatpak0 1.8.2-1ubuntu0.1
Ubuntu 20.04 LTS:
flatpak 1.6.5-0ubuntu0.2
libflatpak0 1.6.5-0ubuntu0.2
Ubuntu 18.04 LTS:
flatpak 1.0.9-0ubuntu0.2
libflatpak0 1.0.9-0ubuntu0.2
In general, a standard system update will make all the necessary changes.
References:
https://usn.ubuntu.com/4721-1
CVE-2021-21261
Package Information:
https://launchpad.net/ubuntu/+source/flatpak/1.8.2-1ubuntu0.1
https://launchpad.net/ubuntu/+source/flatpak/1.6.5-0ubuntu0.2
https://launchpad.net/ubuntu/+source/flatpak/1.0.9-0ubuntu0.2
