GLSA-202101-21 : Flatpak: Sandbox escape

high Nessus Plugin ID 145369
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VPR Score: 8.1


The remote Gentoo host is missing one or more security-related patches.


The remote host is affected by the vulnerability described in GLSA-202101-21 (Flatpak: Sandbox escape)

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).
Impact :

A remote attacker could entice a user to open a specially crafted Flatpak app possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.
Workaround :

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. It is highly recommended to upgrade.


All Flatpak users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=sys-apps/flatpak-1.10.0'

See Also

Plugin Details

Severity: High

ID: 145369

File Name: gentoo_GLSA-202101-21.nasl

Version: 1.3

Type: local

Published: 1/25/2021

Updated: 1/29/2021

Risk Information

Risk Factor: High

VPR Score: 8.1

CVSS Score Source: CVE-2021-21261

CVSS v2.0

Base Score: 7.2

Temporal Score: 5.3

Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 8.8

Temporal Score: 7.7

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

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

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:flatpak, cpe:/o:gentoo:linux

Required KB Items: Host/local_checks_enabled, Host/Gentoo/release, Host/Gentoo/qpkg-list

Exploit Ease: No known exploits are available

Patch Publication Date: 1/25/2021

Vulnerability Publication Date: 1/14/2021

Reference Information

CVE: CVE-2021-21261

GLSA: 202101-21