Description
A malicious or compromised Flatpak repository can write attacker-controlled content to arbitrary locations on the host filesystem via extract_extra_data(). On system installs, the write happens as root. Two issues combine: `files/extra` is resolved via path operations that follow symlinks, and blob names from `xa.extra-data-sources` are not sanitized against `..` traversal.
References10
- access.redhat.com/errata/RHSA-2026:80497
- access.redhat.com/errata/RHSA-2026:80498
- access.redhat.com/errata/RHSA-2026:80687
- access.redhat.com/errata/RHSA-2026:89733
- access.redhat.com/errata/RHSA-2026:90364
- access.redhat.com/errata/RHSA-2026:92221
- access.redhat.com/errata/RHSA-2026:92369
- access.redhat.com/errata/RHSA-2026:95493
- access.redhat.com/security/cve/CVE-2026-96275
- bugzilla.redhat.com/show_bug.cgi?id=2539416
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 48 · as of 9 November 2026
- CWE
- CWE-22
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.