CVE-2026-72657

Authorization Bypass Through User-Controlled Key (CWE-639) in Fleet Server can lead to information disclosure via Manipulating User-Controlled Variables (CAPEC-77). The authorization decision for artifact downloads relied on a client-supplied value that was persisted without being validated against the server-side record of the requesting agent's assignment. An authenticated party in possession of a valid enrolled agent credential could therefore retrieve a policy the agent is not assigned to.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://discuss.elastic.co/t/fleet-server-8-19-20-9-4-5-9-5-1-security-update-esa-2026-112/389509	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:elastic:fleet_server::::::::
	cpe:2.3:a:elastic:fleet_server::::::::
	cpe:2.3:a:elastic:fleet_server:9.5.0:::::::*

History

No history.

Information

Published : 2026-08-13 20:17

Updated : 2026-09-04 20:17

NVD link : CVE-2026-72657

Mitre link : CVE-2026-72657

CVE.ORG link : CVE-2026-72657

JSON object : View

Products Affected

elastic

fleet_server

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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