What is CVE-2023-28100?

CVE-2023-28100 is a critical-severity vulnerability in Flatpak, classified under Improper Input Validation. CVSS score: 10.0/10. Published 2023-03-16.

How severe is CVE-2023-28100?

Critical severity. CVSS v3 base score is 10.0 out of 10.

Is CVE-2023-28100 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Improper input validation in Flatpak

CVE-2023-28100

Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. Versions prior to 1.10.8, 1.12.8, 1.14.4, and 1.15.4 contain a vulnerability similar to CVE-2017-5226, but using the `TIOCLINUX` ioctl command instead of `TIOCSTI`. If a Flatpak app is run on a Linux virtual console such as `/dev/tty1`, it can copy text from the virtual console and paste it into the command buffer, from which the command might be run after the Flatpak app has exited. Ordinary graphical terminal emulators like xterm, gnome-terminal and Konsole are unaffected. This vulnerability is specific to the Linux virtual consoles `/dev/tty1`, `/dev/tty2` and so on. A patch is available in versions 1.10.8, 1.12.8, 1.14.4, and 1.15.4. As a workaround, don't run Flatpak on a Linux virtual console. Flatpak is primarily designed to be used in a Wayland or X11 graphical environment.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2023-03-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (57.5th percentile), scored 2026-10-07.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 57.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Flatpak — versions < 1.10.8, >= 1.12.0, < 1.12.8, >= 1.14.0, < 1.14.4

Weakness classification (CWE)

CWE-20 — Improper Input Validation

Public proof-of-concept exploits

References

github.com/flatpak/flatpak/security/advisories/GHSA-7qpw-3vjv-xrqp (Patch, Vendor Advisory)
github.com/flatpak/flatpak/commit/8e63de9a7d3124f91140fc74f8ca9ed73ed53be9 (Patch)
marc.info/ (Mailing List)
security.gentoo.org/glsa/202312-12

Frequently asked questions

What is CVE-2023-28100?: CVE-2023-28100 is a critical-severity vulnerability in Flatpak, classified under Improper Input Validation. CVSS score: 10.0/10. Published 2023-03-16.
How severe is CVE-2023-28100?: Critical severity. CVSS v3 base score is 10.0 out of 10.
Is CVE-2023-28100 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.