Gentoo: GLSA-202101-21: Flatpak: Sandbox escape
Summary
A bug was discovered in the flatpak-portal service that can allow sandboxed applications to execute arbitrary code on the host system (a sandbox escape).
Resolution
All Flatpak users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-apps/flatpak-1.10.0"
References
[ 1 ] CVE-2021-21261 https://nvd.nist.gov/vuln/detail/CVE-2021-21261
Availability
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/202101-21
Concerns
Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users' machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.
Background
Flatpak is a Linux application sandboxing and distribution framework.
Affected Packages
------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 sys-apps/flatpak < 1.10.0 >= 1.10.0
Impact
===== A remote attacker could entice a user to open a specially crafted Flatpak app possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.
Workaround
As a workaround, this vulnerability can be mitigated by preventing the flatpak-portal service from starting, but that mitigation will prevent many Flatpak apps from working correctly. It is highly recommended to upgrade.