CVE-2026-103264

CRITICAL 9.1

Fleet before 4.87.0 Authentication Bypass via Device Identifiers

CVSS Score

9.1

EPSS Score

0.0%

EPSS Percentile

0th

Fleet versions before 4.87.0 contain an authentication bypass vulnerability in the device API that accepts hostnames and hardware serials as authentication tokens in addition to device UUIDs. Unauthenticated attackers who know or guess these non-secret identifiers can authenticate as iOS/iPadOS hosts to read device data and trigger device-scoped actions including software installation and MDM migration.

CWE	CWE-287
Vendor	fleetdm
Product	fleet
Published	Oct 1, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Affected Versions

fleetdm / fleet

0 < 4.87.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/fleetdm/fleet/security/advisories/GHSA-vrc8-2wcx-327f vulncheck.com: https://www.vulncheck.com/advisories/fleet-before-4.87.0-authentication-bypass-via-device-identifiers