Fleet Server 8.19.20, 9.4.5, 9.5.1 Security Update (ESA-2026-112)

Authorization Bypass Through User-Controlled Key in Fleet Server Leading to Information Disclosure

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.

Affected Versions:

  • All versions from 8.3.0 up to and including 8.19.19
  • All versions from 9.0.0 up to and including 9.4.4
  • Version 9.5.0

Affected Configurations:

All configurations are affected

Solutions and Mitigations:

The issue is resolved in versions 8.19.20, 9.4.5 and 9.5.1.

For Users that Cannot Upgrade:

There are no workarounds for this vulnerability.

Indicators of Compromise (IOC)
No specific indicators of compromise have been identified for this vulnerability.

Severity: CVSSv3.1: Medium ( 6.5 ) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVE ID: CVE-2026-72657
Problem Type: CWE-639 - Authorization Bypass Through User-Controlled Key
Impact: CAPEC-77 - Manipulating User-Controlled Variables