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CVE-2026-126402 Fleet before 4.89.0 Broken Access Control via User Administration API

8.6 highEPSS 0.5%

High (8.6) in fleetdm fleet. EPSS 0.5% estimated probability of exploitation activity in the next 30 days.

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Fleet before 4.89.0 contains an incorrect authorization flaw in its user administration API that accepts user creation or modification when the caller administers any one of the assigned teams. Authenticated team administrators can grant users administrator roles on other teams, then deploy software and execute scripts on those teams' hosts.

Severity

CVSS 4.0

8.6 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

7.2 high
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS
0.5% estimated probability of exploitation activity in the next 30 days; 43rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-863 Incorrect Authorization
OWASP Top 10
A01:2025 Broken Access Control
Published
Assigned by
VulnCheck (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
fleetdm fleetbefore 4.89.0

References

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