SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

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.

CRITICAL 9.3EPSS 0.31%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0
9.3 CRITICALCVSS: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/M
EPSS
0.31% probability · 24th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-287
Affected
fleetdm/fleet
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%2 October 2026: 0.32%26 October 2026: 0.31%2 October 202626 October 2026

EPSS moved from 0.3% on 2 October 2026 to 0.3% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.