Quick answers
- Is CVE-2026-72657 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-72657 being exploited in the wild.
- How severe is CVE-2026-72657?
- Medium severity, with a CVSS score of 6.5, published 13 August 2026.
- Which products and versions are affected?
- Elastic Fleet Server 8.3.0 to 8.19.19, 9.0.0 to 9.4.4, 9.5.0.
- Is there a fix for CVE-2026-72657?
- A patch was published on 2026-08-13: Fixed in versions 8.19.20, 9.4.5, and 9.5.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-72657 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-72657?
- Check whether you run Elastic Fleet Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A CWE-639 authorization bypass vulnerability exists in Fleet Server's artifact download mechanism. The authorization decision relies on a client-supplied value that is persisted without validation against the server-side record of the requesting agent's actual policy assignments. An authenticated attacker with a valid enrolled agent credential can manipulate this client-supplied value to retrieve policies belonging to other agents or deployments. The vulnerability affects all configurations and versions 8.3.0–8.19.19, 9.0.0–9.4.4, and 9.5.0. No authentication bypass is required; the attacker must already possess valid enrolled agent credentials. The fix is available in versions 8.19.20, 9.4.5, and 9.5.1.
Affected products
- Elastic Fleet Server 8.3.0 to 8.19.19, 9.0.0 to 9.4.4, 9.5.0
Timeline
- 2026-08-13: disclosed
- 2026-08-13: patched: Fixed in versions 8.19.20, 9.4.5, and 9.5.1