CVE-2026-34389Published

Fleet's user account creation via invite does not enforce invited email address

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

cve-program · CVE-2026-34389

Published

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.

Source published: 27 Mar 2026 19:18:19 UTC
Source modified: 30 Mar 2026 19:01:30 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 4.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

euvd · EUVD-2026-16797

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Mar 27, 2026, 7:18:19 PM

dateUpdated: Mar 30, 2026, 7:01:30 PM

Source published: Mar 27, 2026, 7:18:19 PM (timezone not stated)
Source modified: Mar 30, 2026, 7:01:30 PM (timezone not stated)
Observed here: 1 Nov 2026 06:06:09 UTC
Source terms: ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 4.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

nvd · CVE-2026-34389

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Analyzed

Weakness classifications: CWE-287

Original publisher date fields

published: 2026-03-27T20:16:35.957

lastModified: 2026-10-26T21:10:00.170

1 source CPE criteria · context only

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

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 27 Mar 2026 20:16:35 UTC
Source modified: 26 Oct 2026 21:10:00 UTC
Observed here: 27 Oct 2026 09:03:00 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 4.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/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

CVSS 3.1 · [email protected] · Primary · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

osv · GHSA-4f9r-x588-pp2h

Published

### Summary 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. ### Impact If an attacker gains access to a valid invite token, they can create a Fleet user account with an email address of their choosing while inheriting the invite’s assigned role and team memberships. This issue: - Requires possession of a valid invite token - Does not bypass authentication controls beyond invite-based account creation - Does not expose data without successful account creation ### Workarounds If upgrading immediately is not possible: - Treat invite links as sensitive credentials and avoid sharing them in public or semi-public channels (e.g., Slack, Teams). - Revoke and reissue invites if there is any concern that an invite link may have been exposed. - Prefer issuing invites with the minimum required privileges and elevating roles after account creation when appropriate. ### For more information If there are any questions or comments about this advisory: Send an email to [[email protected]](mailto:[email protected]) ### Credits Fleet thanks @fuzzztf for responsibly reporting this issue.

Source published: 30 Mar 2026 19:29:13 UTC
Source modified: 2 Apr 2026 21:26:23 UTC
Observed here: 24 Oct 2026 13:19:41 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

Publisher rating · MODERATE

osv · GO-2026-4912

Published

Fleet's user account creation via invite does not enforce invited email address in github.com/fleetdm/fleet

Source published: 2 Apr 2026 18:42:30 UTC
Source modified: 2 Apr 2026 21:20:08 UTC
Observed here: 24 Oct 2026 13:19:41 UTC
Source terms: OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.