---
id: CVE-2026-97026
title: >-
  Flatpak creates temporary child repository directories under the user cache
  with world-writable permissions (0777)
summary: >-
  Flatpak creates temporary child repository directories under the user cache
  with world-writable permissions (0777). On multi-user systems with a
  permissive umask, other local users could read or modify the temporary
  directory used while …
severity: low
cvss: 3.9
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L'
cwe:
  - CWE-378
vendor: Red Hat
product: flatpak
affected:
  - flatpak (all versions)
  - flatpak (all versions)
  - flatpak (all versions)
  - flatpak (all versions)
published: '2026-09-28'
updated: '2026-09-28'
sourceUpdated: '2026-09-28T21:17:19.907'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97026'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-97026'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2542637'
    label: secalert@redhat.com
  - url: 'https://github.com/flatpak/flatpak/security/advisories/GHSA-r9w3-qx54-qvc8'
    label: secalert@redhat.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-28T21:20:54.788Z'
---

## Overview

Flatpak creates temporary child repository directories under the user cache with world-writable permissions (0777). On multi-user systems with a permissive umask, other local users could read or modify the temporary directory used while installing apps or runtimes, potentially causing installation failures (denial of service); tampered content would fail signature/digest verification rather than being trusted.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.