How severe is CVE-2026-34389?

CVE-2026-34389 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-34389 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34389?

CVE-2026-34389 affects Fleetdm Fleet. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34389?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-34389 have an EU (EUVD) identifier?

Yes. CVE-2026-34389 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16797.

When was CVE-2026-34389 published?

CVE-2026-34389 was published on 2026-03-27 and last updated on 2026-06-17.

CVE-2026-34389

CVE-2026-34389 is a medium-severity vulnerability in Fleetdm Fleet with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 4.9
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16797
Weakness: CWE-287
Affected product: Fleetdm Fleet
Published: 2026-03-27
Last modified: 2026-06-17

Description

Fleet is open source device management software. Prior to 4.81.0, Fleet contained an issue in the user invitation flow where the email address provided during invite acceptance was not validated against the email address associated with the invite. An attacker who obtained a valid invite token could create an account under an arbitrary email address while inheriting the role granted by the invite, including global admin. Version 4.81.0 patches the issue.

Frequently asked questions

What is CVE-2026-34389?: Fleet is open source device management software. Prior to 4.81.0, Fleet contained an issue in the user invitation flow where the email address provided during invite acceptance was not validated against the email address associated with the invite. An attacker who obtained a valid invite token could create an account under an arbitrary email address while inheriting the role granted by the invite, including global admin. Version 4.81.0 patches the issue.
How severe is CVE-2026-34389?: CVE-2026-34389 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-34389 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34389?: CVE-2026-34389 affects Fleetdm Fleet. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34389?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34389 have an EU (EUVD) identifier?: Yes. CVE-2026-34389 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16797.
When was CVE-2026-34389 published?: CVE-2026-34389 was published on 2026-03-27 and last updated on 2026-06-17.

References

https://github.com/fleetdm/fleet/security/advisories/GHSA-4f9r-x588-pp2h

Affected products (1)

cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*

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