CVE-2026-97026
Flatpak: flatpak: world-writable temporary child repositories in system-helper cache path
- 3.9LowCVSS base score
- 0.10%Exploitation in 30 daysEPSS · top 99% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By redhat
- 5 days later
· 5 days later
Published
- 39 days later
· 39 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Low3.9 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L |
| NVDNVD · Awaiting Analysis | 3.1 | Low3.9 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.10% · top 99% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.9.
Affected products
Red Hat · Red Hat Enterprise Linux 10
All versions: affected
Red Hat · Red Hat Enterprise Linux 7
All versions: affected
Red Hat · Red Hat Enterprise Linux 8
All versions: affected
Red Hat · Red Hat Enterprise Linux 9
All versions: affected
What to do
Workaround: Set a umask that does not allow other users to write to the cache directory, for example: umask 022. Note that a umask that does not allow read/exec access by all (for example 027 or 077) will prevent the flatpak-system-helper from reading the temporary directory directly, resulting in falling back to copying the repository inefficiently, with a warning.
References
References3
- https://access.redhat.com/security/cve/CVE-2026-97026 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2542637 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://github.com/flatpak/flatpak/security/advisories/GHSA-r9w3-qx54-qvc8 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-88553 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-97026)Record last updated .