Description
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.
References3
Metrics
- CVSS 3.1
-
3.9
LOW
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L - EPSS — exploit probability
- 0% percentile: 1 · as of 9 November 2026
- CWE
- CWE-378
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