CVE-2026-78587

lowpriority · track · 0OT risk · elevatedEPSS 0.003 · 22 %ileUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.29% (22nd) EPSS

CVSS 3.1 · low

Is it mine?

3 products

Check your exposure

Who says so?

1 sources

nvd

EPSS · scored 2026-10-28

Incorrect Authorization (CWE-863) in Fleet Server can lead to a denial of service of agent upload operations via Privilege Abuse (CAPEC-122). Fleet Server does not correctly verify session ownership during multi-part data upload operations, allowing any authenticated agent to interfere with the active upload sessions belonging to other enrolled agents.

cvss

Technical severity, 0–10. One row per scoring source.

3.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.13.1lowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · security@elastic.coexploitability 1.6 · impact 1.4

v3.12.9lowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-863US

affected products (3)

Products and version ranges known to be affected.

elastic fleet server8.0.0 → 8.19.16nvdUScpe:2.3:a:elastic:fleet_server:*:*:*:*:*:*:*:*
elastic fleet server9.0.0 → 9.3.5nvdUScpe:2.3:a:elastic:fleet_server:*:*:*:*:*:*:*:*
elastic fleet server9.4.0 → 9.4.2nvdUScpe:2.3:a:elastic:fleet_server:*:*:*:*:*:*:*:*

sources

Which sources assert this record, and when.

nvd NVD CVE.org MITRE

published 2026-09-02modified 2026-09-03

references (1) nvd

External citations — patches, advisories, analysis.

https://discuss.elastic.co/t/fleet-server-8-19-16-9-3-5-9-4-2-security-update-esa-2026-164/390117Vendor Advisory

scry

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