CVE-2021-21261

Katalog CVE

CVSS 8.8 · High EPSS 0,60%

Kerentanan Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') pada flatpak, debian linux. Skor CVSS 3.1 8.8 (High) menurut NVD.

Deskripsi (NVD)

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.

Rincian

Terbit di NVD

14 Januari 2021

Terakhir diubah

17 Juni 2026

Status NVD

Modified

CVSS 3.1

8.8 (High), sumber NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

EPSS (30 hari)

0,60% peluang dieksploitasi; lebih tinggi dari 47,0% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/flatpak/flatpak/commit/6d1773d2a54dde9b099043f07a2094a4f1c2f486 patch · advisory pihak ketiga
• https://github.com/flatpak/flatpak/commit/6e5ae7a109cdfa9735ea7ccbd8cb79f9e8d3ae8b patch · advisory pihak ketiga
• https://github.com/flatpak/flatpak/commit/aeb6a7ab0abaac4a8f4ad98b3df476d9de6b8bd4 patch · advisory pihak ketiga
• https://github.com/flatpak/flatpak/commit/cc1401043c075268ecc652eac557ef8076b5eaba advisory pihak ketiga
• https://github.com/flatpak/flatpak/releases/tag/1.8.5 advisory pihak ketiga
• https://github.com/flatpak/flatpak/security/advisories/GHSA-4ppf-fxf6-vxg2 advisory pihak ketiga
• https://security.gentoo.org/glsa/202101-21 advisory pihak ketiga
• https://www.debian.org/security/2021/dsa-4830 advisory pihak ketiga