What is CVE-2026-34391?

CVE-2026-34391 is a high-severity vulnerability in Fleetdm Fleet, classified under CWE-488. CVSS score: 7.5/10. Published 2026-03-27.

How severe is CVE-2026-34391?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Fleetdm Fleet

CVE-2026-34391

Fleet is open source device management software. Prior to 4.81.1, a vulnerability in Fleet's Windows MDM command processing allows a malicious enrolled device to access MDM commands intended for other devices, potentially exposing sensitive configuration data such as WiFi credentials, VPN secrets, and certificate payloads across the entire Windows fleet. Version 4.81.1 patches the issue.

Published 2026-03-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (17.0th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Fleetdm Fleet — versions < 4.81.1

Weakness classification (CWE)

CWE-488

References

github.com/fleetdm/fleet/security/advisories/GHSA-wg7j-pcc3-h4rh (Vendor Advisory)

Frequently asked questions

What is CVE-2026-34391?: CVE-2026-34391 is a high-severity vulnerability in Fleetdm Fleet, classified under CWE-488. CVSS score: 7.5/10. Published 2026-03-27.
How severe is CVE-2026-34391?: High severity. CVSS v3 base score is 7.5 out of 10.