What’s Vulnerable › Vulnerabilities
CVE-2026-72657: Authorization Bypass Through User-Controlled Key in Fleet Server Leading to Information Disclosure
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-08-13 · updated 2026-09-04
- Weakness: CWE-639
Description
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 products
- Elastic Fleet Server: from 8.3.0 before 8.19.20; from 9.0.0 before 9.4.5; 9.5.0 — fixed in 8.19.20, 9.4.5
How to fix
Upgrade to a fixed version: Elastic Fleet Server 8.19.20, 9.4.5. Check the vendor advisory for mitigations.
References
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