SB2026041101 - Fedora 43 update for flatpak



SB2026041101 - Fedora 43 update for flatpak

Published: April 11, 2026

Security Bulletin ID SB2026041101
CSH Severity
High
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Improper access control (CVE-ID: CVE-2026-34078)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber


The vulnerability allows a remote attacker to execute code in the host context.

The vulnerability exists due to improper access control in the Flatpak portal and flatpak run when processing sandbox-expose options containing app-controlled symlinks. A remote attacker can supply a crafted path to gain access to arbitrary host files and execute code in the host context.

The issue enables sandbox escape from a Flatpak app to the host environment.


2) Path traversal (CVE-ID: CVE-2026-34079)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to delete arbitrary files on the host filesystem.

The vulnerability exists due to improper path validation in ld.so cache file caching when removing outdated cache files. A local user can control the path to an outdated cache file to delete arbitrary files on the host filesystem.


Remediation

Install update from vendor's website.