Amazon Linux 2 : flatpak (ALAS-2023-2076)

high Nessus Plugin ID 176897

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of flatpak installed on the remote host is prior to 1.0.9-10. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2023-2076 advisory.

- 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. (CVE-2021-41133)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update flatpak' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2023-2076.html

https://alas.aws.amazon.com/cve/html/CVE-2021-41133.html

https://alas.aws.amazon.com/faqs.html

Plugin Details

Severity: High

ID: 176897

File Name: al2_ALAS-2023-2076.nasl

Version: 1.0

Type: local

Agent: unix

Published: 6/8/2023

Updated: 6/8/2023

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-41133

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:flatpak, p-cpe:/a:amazon:linux:flatpak-libs, p-cpe:/a:amazon:linux:flatpak-debuginfo, p-cpe:/a:amazon:linux:flatpak-devel, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:flatpak-builder

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 6/5/2023

Vulnerability Publication Date: 10/8/2021

Reference Information

CVE: CVE-2021-41133