# CVE-2026-96281: Flatpak: flatpak: unprivileged active user can bypass anti-downgrade checks for system apps/runtimes

Status: published. Published: 2026-09-27. Updated: 2026-11-06.

On a multi-user system, a user with an active local login session could downgrade a system-wide Flatpak app to an older version by removing the app's remote ref via the unprivileged system-helper RemoveLocalRef method, causing the anti-downgrade check to fail to find a reference date. A malicious local user could use this to expose other users of the same system to an app version with unfixed vulnerabilities.

## Remediation

- workaround: Ensure that Flatpak apps installed system-wide are fully updated before running them. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (flatpak): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (flatpak): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (flatpak): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (flatpak): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.2 (medium); CVSS:3.1/AV:P/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.12% as of 2026-11-05; percentile 2.13%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-284

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/security/cve/CVE-2026-96281 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2539421 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://github.com/flatpak/flatpak/security/advisories/GHSA-q4gr-vc25-57m5 (CNA: redhat)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-96281; retrieved 2026-11-06; source updated 2026-11-06

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-96281; retrieved 2026-11-06; source updated Not reported

Revision: 5bcbbd2a5c35e82419aab5b0ce72819f8ad4218213f0839ae1992d81b5e11c89

Canonical: https://y2.dev/cve/CVE-2026-96281

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