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SUSE: CVE-2021-21261: SUSE Linux Security Advisory

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SUSE: CVE-2021-21261: SUSE Linux Security Advisory



Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. 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). This sandbox-escape bug is present in versions from 0.11.4 and before fixed versions 1.8.5 and 1.10.0. The Flatpak portal D-Bus service (`flatpak-portal`, also known by its D-Bus service name `org.freedesktop.portal.Flatpak`) allows apps in a Flatpak sandbox to launch their own subprocesses in a new sandbox instance, either with the same security settings as the caller or with more restrictive security settings. For example, this is used in Flatpak-packaged web browsers such as Chromium to launch subprocesses that will process untrusted web content, and give those subprocesses a more restrictive sandbox than the browser itself. In vulnerable versions, the Flatpak portal service passes caller-specified environment variables to non-sandboxed processes on the host system, and in particular to the `flatpak run` command that is used to launch the new sandbox instance. A malicious or compromised Flatpak app could set environment variables that are trusted by the `flatpak run` command, and use them to execute arbitrary code that is not in a sandbox. 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. This is fixed in versions 1.8.5 and 1.10.0.


  • suse-upgrade-flatpak
  • suse-upgrade-flatpak-devel
  • suse-upgrade-flatpak-zsh-completion
  • suse-upgrade-libflatpak0
  • suse-upgrade-libostree
  • suse-upgrade-libostree-1-1
  • suse-upgrade-libostree-devel
  • suse-upgrade-libostree-grub2
  • suse-upgrade-system-user-flatpak
  • suse-upgrade-typelib-1_0-flatpak-1_0
  • suse-upgrade-typelib-1_0-ostree-1_0
  • suse-upgrade-xdg-desktop-portal
  • suse-upgrade-xdg-desktop-portal-devel
  • suse-upgrade-xdg-desktop-portal-gtk
  • suse-upgrade-xdg-desktop-portal-gtk-lang
  • suse-upgrade-xdg-desktop-portal-lang

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