CVE-2026-34391: Fleet is open source device management software

Q: How do I fix CVE-2026-34391?

fleet: upgrade to 4.81.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-34391 being exploited?

CVE-2026-34391 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-34391 affect?

CVE-2026-34391 affects fleet. Severity is high (CVSS 7.5). 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

Q: How urgent is CVE-2026-34391?

Priority 33/100. High severity; Remotely exploitable, no login, no user action

Routine

HIGH 7.5REMOTEUPGRADE

CVE-2026-34391 is a high-severity flaw (CVSS 7.5) affecting fleet. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.2% (top 94%)
CISA exploited list	No
Weakness	CWE-488
Published	2026-03-27
Last modified	2026-10-26

Publisher (CNA): GitHub, Inc. · Vendor: fleetdm

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-27 20:16 UTCPublished CVE record published
2026-10-26 22:10 UTCUpdated Record last modified

fleetdm fleet UPGRADE

Affected: < 4.81.1

Fixed in: 4.81.1

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy fleet || rpm -q fleet || fleet --version

2. UPGRADE to 4.81.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade fleet

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade fleet

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-34391?

fleet: upgrade to 4.81.1. Exact commands for each OS are on this page.

Is CVE-2026-34391 being exploited?

CVE-2026-34391 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-34391 affect?

CVE-2026-34391 affects fleet. Severity is high (CVSS 7.5). 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

How urgent is CVE-2026-34391?

Priority 33/100. High severity; Remotely exploitable, no login, no user action

Software pages

Windows vulnerabilities · Wi-Fi vulnerabilities

Related CVEs

CVE-2026-34387 CRITICAL 9.8 UPGRADE Fleet is open source device management software
CVE-2026-29180 HIGH 8.8 UPGRADE Fleet is open source device management software
CVE-2026-34386 HIGH 8.8 UPGRADE Fleet is open source device management software
CVE-2026-34385 HIGH 8.1 UPGRADE Fleet is open source device management software
CVE-2026-26061 HIGH 7.5 UPGRADE Fleet is open source device management software

References

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