Medium [CVE-2026-96279] Flatpak: flatpak: path traversal issue in oci archive extraction via hardlinks
This medium-severity Red Hat Linux advisory covers CVE-2026-96279 affecting Red Hat Enterprise Linux 10, Red Hat package: flatpak.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
A malicious OCI registry can hardlink arbitrary host files into the extraction directory when a user installs or updates a Flatpak application from an OCI remote, allowing disclosure of arbitrary host file contents. For system-wide installs running as root, this includes sensitive files such as /etc/shadow.
Red Hat estimates the CVSSv3.1 vector of CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N. The malicious archive is served over the network (AV:N), and the attacker needs no privileges of their own on the victim system (PR:N).
Once the client pulls the crafted layer archive, exploitation is deterministic: Flatpak's OCI extraction rebases archive entry pathnames to the destination directory and enforces ARCHIVE_EXTRACT_SECURE_NODOTDOT to reject.. in pathnames and hardlink targets, but it fails to rebase the hardlink target itself, so a crafted entry with an absolute hardlink target (e.g. /etc/shadow) causes libarchive to hardlink that host file directly into the extraction directory (AC:L).
Meaningful user interaction is required (UI:R). On system-wide installs, this extraction runs via the privileged system-helper as root, so the hardlinked file can be an arbitrary root-owned file the attacker has no other means to access.
Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat package: flatpak.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 2 days ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 2 days ago·verify at source
Mitigation checklist
- Only install applications from trusted OCI registries. Flatpak remotes using the default OSTree transport are not affected.
Official advisory · high-confidence parse· fetched 2 days ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.