CVE-2026-34389Network attack vector

Privileged account creation via unchecked invite email

Published Mar 27, 2026 · Updated Mar 27, 2026

Improper authentication in Fleet before 4.81.0 allows remote attackers with a valid invite token to create an account with the invite's role. The invite acceptance flow accepts a caller-supplied email address without comparing it to the address stored for the token, then assigns the token's role and team memberships to the new account. Possession of an unexpired invite token is required, and the resulting account can obtain any role carried by that invite, including global admin, but receives no access until account creation succeeds.

CVSS severity6.5
Medium
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Fleet before 4.81.0 allows remote attackers with a valid invite token to create an account with the invite's role. The invite acceptance flow accepts a caller-supplied email address without comparing it to the address stored for the token, then assigns the token's role and team memberships to the new account. Possession of an unexpired invite token is required, and the resulting account can obtain any role carried by that invite, including global admin, but receives no access until account creation succeeds.

The record

CVE
CVE-2026-34389
Published
Mar 27, 2026
Updated
Mar 27, 2026
Vendor
Fleet Device Management
Product
Fleet
Classifications
CWE-287, T1136
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.81.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fleet Device Management · Fleetversion=< 4.81.0

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
4.9GitHub, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1136Create Account

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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