Vulnerability Name:

CVE-2021-21261 (CCN-194967)

Assigned:2020-12-22
Published:2021-01-14
Updated:2021-01-27
Summary:Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. 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). This sandbox-escape bug is present in versions from 0.11.4 and before fixed versions 1.8.5 and 1.10.0. The Flatpak portal D-Bus service (`flatpak-portal`, also known by its D-Bus service name `org.freedesktop.portal.Flatpak`) allows apps in a Flatpak sandbox to launch their own subprocesses in a new sandbox instance, either with the same security settings as the caller or with more restrictive security settings. For example, this is used in Flatpak-packaged web browsers such as Chromium to launch subprocesses that will process untrusted web content, and give those subprocesses a more restrictive sandbox than the browser itself. In vulnerable versions, the Flatpak portal service passes caller-specified environment variables to non-sandboxed processes on the host system, and in particular to the `flatpak run` command that is used to launch the new sandbox instance. A malicious or compromised Flatpak app could set environment variables that are trusted by the `flatpak run` command, and use them to execute arbitrary code that is not in a sandbox. 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. This is fixed in versions 1.8.5 and 1.10.0.
CVSS v3 Severity:8.8 High (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H)
7.7 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
8.8 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H)
7.7 High (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
8.8 High (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H)
7.7 High (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
CVSS v2 Severity:7.2 High (CVSS v2 Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): Complete
6.8 Medium (CCN CVSS v2 Vector: AV:L/AC:L/Au:S/C:C/I:C/A:C)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): Complete
Vulnerability Type:CWE-74
CWE-77
Vulnerability Consequences:Gain Access
References:Source: MITRE
Type: CNA
CVE-2021-21261

Source: XF
Type: UNKNOWN
flatpak-cve202121261-code-exec(194967)

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/flatpak/flatpak/commit/6d1773d2a54dde9b099043f07a2094a4f1c2f486

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/flatpak/flatpak/commit/6e5ae7a109cdfa9735ea7ccbd8cb79f9e8d3ae8b

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/flatpak/flatpak/commit/aeb6a7ab0abaac4a8f4ad98b3df476d9de6b8bd4

Source: MISC
Type: Third Party Advisory
https://github.com/flatpak/flatpak/commit/cc1401043c075268ecc652eac557ef8076b5eaba

Source: MISC
Type: Third Party Advisory
https://github.com/flatpak/flatpak/releases/tag/1.8.5

Source: CCN
Type: Flatpak GIT Repository
CVE-2021-21261: Flatpak sandbox escape via spawn portal

Source: CONFIRM
Type: Third Party Advisory
https://github.com/flatpak/flatpak/security/advisories/GHSA-4ppf-fxf6-vxg2

Source: GENTOO
Type: Third Party Advisory
GLSA-202101-21

Source: DEBIAN
Type: Third Party Advisory
DSA-4830

Vulnerable Configuration:Configuration 1:
  • cpe:/a:flatpak:flatpak:*:*:*:*:*:*:*:* (Version >= 0.11.4 and < 1.8.5)
  • OR cpe:/a:flatpak:flatpak:*:*:*:*:*:*:*:* (Version >= 1.9.1 and < 1.10.0)

    • Configuration 2:
  • cpe:/o:debian:debian_linux:10.0:*:*:*:*:*:*:*

    • Configuration RedHat 1:
  • cpe:/a:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 2:
  • cpe:/a:redhat:enterprise_linux:8::appstream:*:*:*:*:*

    • Configuration RedHat 3:
  • cpe:/o:redhat:enterprise_linux:7:*:*:*:*:*:*:*

    • Configuration RedHat 4:
  • cpe:/o:redhat:enterprise_linux:7::client:*:*:*:*:*

    • Configuration RedHat 5:
  • cpe:/o:redhat:enterprise_linux:7::computenode:*:*:*:*:*

    • Configuration RedHat 6:
  • cpe:/o:redhat:enterprise_linux:7::server:*:*:*:*:*

    • Configuration RedHat 7:
  • cpe:/o:redhat:enterprise_linux:7::workstation:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/a:flatpak:flatpak:0.11.4:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:org.opensuse.security:def:7885
    P
    		flatpak-1.14.4-150500.1.3 on GA media (Moderate)
    2023-06-12
    oval:org.opensuse.security:def:3372
    P
    		stunnel-5.00-4.3.4 on GA media (Moderate)
    2022-06-28
    oval:org.opensuse.security:def:3268
    P
    		libtiff5-32bit-4.0.9-44.30.1 on GA media (Moderate)
    2022-06-28
    oval:org.opensuse.security:def:94898
    P
    		flatpak-1.12.5-150400.1.11 on GA media (Moderate)
    2022-06-22
    oval:org.opensuse.security:def:94761
    P
    		openslp-2.0.0-6.15.1 on GA media (Moderate)
    2022-06-22
    oval:org.opensuse.security:def:95185
    P
    		evolution-data-server-3.42.4-150400.1.7 on GA media (Moderate)
    2022-06-22
    oval:org.opensuse.security:def:1653
    P
    		Security update for salt (Important)
    2022-03-30
    oval:org.opensuse.security:def:101898
    P
    		Security update for java-1_8_0-openjdk (Important)
    2022-03-16
    oval:org.opensuse.security:def:94484
    P
    		 (Moderate)
    2022-03-14
    oval:org.opensuse.security:def:112240
    P
    		flatpak-1.11.3-1.2 on GA media (Moderate)
    2022-01-17
    oval:org.opensuse.security:def:105770
    P
    		flatpak-1.11.3-1.2 on GA media (Moderate)
    2021-10-01
    oval:org.opensuse.security:def:101148
    P
    		flatpak-1.10.2-4.6.1 on GA media (Moderate)
    2021-08-09
    oval:org.opensuse.security:def:72461
    P
    		flatpak-1.10.2-4.6.1 on GA media (Moderate)
    2021-08-09
    oval:org.opensuse.security:def:101197
    P
    		libjasper-devel-2.0.14-3.19.1 on GA media (Moderate)
    2021-08-09
    oval:org.opensuse.security:def:62742
    P
    		flatpak-1.10.2-4.6.1 on GA media (Moderate)
    2021-08-09
    oval:org.opensuse.security:def:101474
    P
    		Security update for the Linux Kernel (Important)
    2021-07-20
    oval:org.opensuse.security:def:111306
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-09
    oval:org.opensuse.security:def:73583
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:108140
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:64461
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:4116
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:74273
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:108564
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:65205
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:5637
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:117378
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:75794
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:96825
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:66726
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:107863
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:org.opensuse.security:def:117654
    P
    		Security update for flatpak, libostree, xdg-desktop-portal, xdg-desktop-portal-gtk (Important)
    2021-04-07
    oval:com.redhat.rhsa:def:20210411
    P
    		RHSA-2021:0411: flatpak security update (Important)
    2021-02-04
    oval:com.redhat.rhsa:def:20210304
    P
    		RHSA-2021:0304: flatpak security update (Important)
    2021-02-01
    BACK
    flatpak flatpak *
    flatpak flatpak *
    debian debian linux 10.0
    flatpak flatpak 0.11.4