CVE-2021-41133

HIGH
Published Oct 8, 20214y ago · Modified Jun 17, 20262w ago
7.8 CVSS 3.1
High
Find Similar
Published Oct 8, 2021 4y ago
Last Modified Jun 17, 2026 2w ago

Description

Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. In versions prior to 1.10.4 and 1.12.0, Flatpak apps with direct access to AF_UNIX sockets such as those used by Wayland, Pipewire or pipewire-pulse can trick portals and other host-OS services into treating the Flatpak app as though it was an ordinary, non-sandboxed host-OS process. They can do this by manipulating the VFS using recent mount-related syscalls that are not blocked by Flatpak's denylist seccomp filter, in order to substitute a crafted `/.flatpak-info` or make that file disappear entirely. Flatpak apps that act as clients for AF_UNIX sockets such as those used by Wayland, Pipewire or pipewire-pulse can escalate the privileges that the corresponding services will believe the Flatpak app has. Note that protocols that operate entirely over the D-Bus session bus (user bus), system bus or accessibility bus are not affected by this. This is due to the use of a proxy process `xdg-dbus-proxy`, whose VFS cannot be manipulated by the Flatpak app, when interacting with these buses. Patches exist for versions 1.10.4 and 1.12.0, and as of time of publication, a patch for version 1.8.2 is being planned. There are no workarounds aside from upgrading to a patched version.

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-20 Improper Input Validation Validation

Affected Products 6

VendorProductVersionRange
flatpakflatpak* <1.8.2
flatpakflatpak*≥1.10.0  –  <1.10.4
flatpakflatpak*≥1.11.1  –  <1.12.1
debiandebian_linux11.0any
fedoraprojectfedora33any
fedoraprojectfedora34any

References 14

  • openwall.com http://www.openwall.com/lists/oss-security/2021/10/26/9
    Mailing ListThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/1330662f33a55e88bfe18e76de28b7922d91a999
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/26b12484eb8a6219b9e7aa287b298a894b2f34ca
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/462fca2c666e0cd2b60d6d2593a7216a83047aaf
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/4c34815784e9ffda5733225c7d95824f96375e36
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/89ae9fe74c6d445bb1b3a40e568d77cf5de47e48
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/9766ee05b1425db397d2cf23afd24c7f6146a69f
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/a10f52a7565c549612c92b8e736a6698a53db330
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/e26ac7586c392b5eb35ff4609fe232c52523b2cf
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/security/advisories/GHSA-67h7-w3jq-vh4q
    PatchThird Party Advisory
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R5656ONDP2MGKIJMKEC7N2NXCV27WGTC/
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T5DKCYRC6MFSTFCUP4DELCOUUP3SFEFX/
  • security.gentoo.org https://security.gentoo.org/glsa/202312-12
  • debian.org https://www.debian.org/security/2021/dsa-4984
    Third Party Advisory

Remediation

  • github.com https://github.com/flatpak/flatpak/commit/1330662f33a55e88bfe18e76de28b7922d91a999
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/26b12484eb8a6219b9e7aa287b298a894b2f34ca
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/462fca2c666e0cd2b60d6d2593a7216a83047aaf
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/4c34815784e9ffda5733225c7d95824f96375e36
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/89ae9fe74c6d445bb1b3a40e568d77cf5de47e48
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/9766ee05b1425db397d2cf23afd24c7f6146a69f
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/a10f52a7565c549612c92b8e736a6698a53db330
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/commit/e26ac7586c392b5eb35ff4609fe232c52523b2cf
    PatchThird Party Advisory
  • github.com https://github.com/flatpak/flatpak/security/advisories/GHSA-67h7-w3jq-vh4q
    PatchThird Party Advisory