SECURELYN

CVE-2026-103264

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.

Scores

9.3
CVSS 9.3 out of 10, critical severity.
0.3%
EPSS 0.3% chance of exploitation in the next 30 days.

The facts

Published
1 October 2026
Last changed
8 October 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.3 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/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…
Weakness
Affects
  • fleetdm fleet
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.3% chance of exploitation activity in the next 30 days (percentile 22).

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References