CVE-2026-78587

Incorrect Authorization in Fleet Server Leading to Denial of Service of Agent Upload Operations

LOW
3.1
CVSS Score
Published: September 2, 2026 at 02:43 PM UTC
Updated: September 3, 2026 at 07:24 PM UTC
1 product affected across 1 vendorFleet Server

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Severity
LOW3.1
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

95%
8.0.0 ≤ v ≤ 8.19.158.0.0 ≤ v < 8.19.169.0.0 ≤ v ≤ 9.3.49.0.0 ≤ v < 9.3.59.4.0 ≤ v ≤ 9.4.19.4.0 ≤ v < 9.4.28.0.09.0.09.4.0
Affected range stops below 8.19.16, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.3.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.4.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

3.1LOWelastic
Attack Vector
NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusANALYZED
CWE
CWE-863

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