Flatpak: flatpak: arbitrary write access as root via extra-data extraction
A malicious or compromised Flatpak repository can write attacker-controlled content to arbitrary locations on the host filesystem via extract_extra_data().
flatpak security update
Released 2026-10-29 · Red Hat rating Important · View on Red Hat →
A malicious or compromised Flatpak repository can write attacker-controlled content to arbitrary locations on the host filesystem via extract_extra_data().
The OCI delta stream parser read sizes as guint64 but passed them to GLib I/O and allocation functions expecting gsize (32 bits on 32-bit systems), causing undersized allocations while subsequent operations use the origi…
In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026…
In Flatpak before 1.18.1, the revokefs writer, used by the flatpak-system-helper to receive repository data from unprivileged callers, validated file paths by rejecting literal ..