CVE-2026-34078
Publication date 7 April 2026
Last updated 30 June 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| flatpak | 26.04 LTS resolute |
Not affected
|
| 24.04 LTS noble |
Vulnerable
|
|
| 22.04 LTS jammy |
Vulnerable
|
|
| 20.04 LTS focal |
Vulnerable
|
|
| 18.04 LTS bionic |
Vulnerable
|
Severity score breakdown
CVSS version:
Base score
9.3 · Critical
Vector: 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
Base score
9.0 · Critical
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H