CVE-2021-41133

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

08/10/2021

Last modified:

23/12/2023

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&#39;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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

7.80

Severity 3.x

HIGH

Vector 2.0

AV:L/AC:L/Au:N/C:P/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 4.60 MEDIUM
Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P

Attack Vector (AV): Local
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): Physical
Integrity (I): Physical
Availability (A): Physical

Base Score 2.0

4.60

Severity 2.0

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:flatpak:flatpak::::::::		1.8.2 (excluding)
cpe:2.3:a:flatpak:flatpak::::::::	1.10.0 (including)	1.10.4 (excluding)
cpe:2.3:a:flatpak:flatpak::::::::	1.11.1 (including)	1.12.1 (excluding)
cpe:2.3:o:debian:debian_linux:11.0:::::::*
cpe:2.3:o:fedoraproject:fedora:33:::::::*
cpe:2.3:o:fedoraproject:fedora:34:::::::*

To consult the complete list of CPE names with products and versions, see this page

CVE-2021-41133

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools