CVE-2022-21682

CVE Details

Release Date:	2022-01-13
Impact:	None	What is this?

Description

Flatpak is a Linux application sandboxing and distribution framework. A path traversal vulnerability affects versions of Flatpak prior to 1.12.3 and 1.10.6. flatpak-builder applies finish-args last in the build. At this point the build directory will have the full access that is specified in the manifest, so running flatpak build against it will gain those permissions. Normally this will not be done, so this is not problem. However, if --mirror-screenshots-url is specified, then flatpak-builder will launch flatpak build --nofilesystem=host appstream-utils mirror-screenshots after finalization, which can lead to issues even with the --nofilesystem=host protection. In normal use, the only issue is that these empty directories can be created wherever the user has write permissions. However, a malicious application could replace the appstream-util binary and potentially do something more hostile. This has been resolved in Flatpak 1.12.3 and 1.10.6 by changing the behaviour of --nofilesystem=home and --nofilesystem=host.

See more information about CVE-2022-21682 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	6.5
Vector String:	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Version:	3.0
Attack Vector:	Network
Attack Complexity:	Low
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	High
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (flatpak-builder)	ELSA-2022-7458	2022-11-15