#VU49587 Code Injection in Flatpak - CVE-2021-21261
Published: January 14, 2021 / Updated: January 18, 2021
Vulnerability identifier: #VU49587
Vulnerability risk: Low
CVSSv4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:U/U:Clear
CVE-ID: CVE-2021-21261
CWE-ID: CWE-94
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Flatpak
Flatpak
Software vendor:
Flatpak
Flatpak
Description
The vulnerability allows a local application to elevate privileges on the system.
The vulnerability exists due to improper input validation when processing environment variables, passed from a sandboxed process to a non-sandboxed process 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 can set environment variables that are trusted by the `flatpak run` command, and use them to execute arbitrary code that is not in a sandbox.
Remediation
Install updates from vendor's website.
External links
- https://github.com/flatpak/flatpak/commit/57416f380600d9754df12baf5b227144ff1bb54d
- https://github.com/flatpak/flatpak/commit/6a11007021658518c088ba0cc5e4da27962a940a
- https://github.com/flatpak/flatpak/commit/dcd24941c7087c5f7e8033abe50b178ac02a34af
- https://github.com/flatpak/flatpak/commit/fb1eaefbceeb73f02eb1bc85865d74a414faf8b8
- https://github.com/flatpak/flatpak/releases/tag/1.8.5
- https://github.com/flatpak/flatpak/security/advisories/GHSA-4ppf-fxf6-vxg2
- https://www.debian.org/security/2021/dsa-4830