CVE-2026-34078
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 1.7% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 1.7% in the next 30 days (EPSS).
- Severity: 9.3 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 1.7% · EPSS, next 30 days
- Weakness
- CWE-61
- Record status
- Modified
Affected
- Flatpak ≤ 1.16.3
Attack profile CVSS 4.0 · 9.3
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw 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/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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-34078.md and follow it. Check whether this project is affected by CVE-2026-34078. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
References
- https://github.com/flatpak/flatpak/security/advisories/GHSA-cc2q-qc34-jprg
- http://www.openwall.com/lists/oss-security/2026/04/09/8
- http://www.openwall.com/lists/oss-security/2026/04/10/14
- https://access.redhat.com/errata/RHSA-2026:21755
- https://access.redhat.com/errata/RHSA-2026:21756
- https://access.redhat.com/errata/RHSA-2026:21757
- https://access.redhat.com/errata/RHSA-2026:23417
- https://access.redhat.com/errata/RHSA-2026:23418
- https://access.redhat.com/errata/RHSA-2026:23419
- https://access.redhat.com/errata/RHSA-2026:23420
- https://access.redhat.com/errata/RHSA-2026:25068
- https://access.redhat.com/errata/RHSA-2026:25381
- https://access.redhat.com/errata/RHSA-2026:30901
- https://access.redhat.com/errata/RHSA-2026:35843
- https://access.redhat.com/security/cve/CVE-2026-34078
- https://bugzilla.redhat.com/show_bug.cgi?id=2456276
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34078.json