Description
Flatpak is a Linux application sandboxing and distribution framework. Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. Flatpak run mounts the resolved host path in the sandbox. This gives apps access to all host files and can be used as a primitive to gain code execution in the host context. This vulnerability is fixed in 1.16.4.
Affected products
flatpak: flatpak
References10
- github.com/flatpak/flatpak/security/advisories/GHSA-cc2q-qc34-j… Vendor Advisory
- www.openwall.com/lists/oss-security/2026/04/09/8 Mailing ListThird Party Advisory
- www.openwall.com/lists/oss-security/2026/04/10/14 Mailing ListThird Party Advisory
- access.redhat.com/errata/RHSA-2026:21755
- access.redhat.com/errata/RHSA-2026:21756
- access.redhat.com/errata/RHSA-2026:21757
- access.redhat.com/errata/RHSA-2026:23417
- access.redhat.com/errata/RHSA-2026:23418
- access.redhat.com/errata/RHSA-2026:23419
- access.redhat.com/errata/RHSA-2026:23420
Metrics
- CVSS 3.1
-
10.0
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 2% percentile: 78 · as of 12 November 2026
- CWE
- CWE-61CWE-59
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