CVE-2026-24000

Fleet is open source device management software. Prior to version 4.80.1, Fleet trusted client-supplied IP address headers when determining the source IP for incoming requests. This allowed authenticated and unauthenticated clients to spoof their apparent IP address and bypass per-IP rate limiting controls. Fleet determines a client’s public IP address using HTTP headers such as X-Forwarded-For, X-Real-IP, and/or True-Client-IP. These headers were trusted without validation. An attacker could supply arbitrary values in these headers, causing Fleet to treat each request as originating from a different IP address. This could allow an attacker to bypass per-IP rate limits and increase the effectiveness of brute-force or password-spraying attempts against authentication endpoints. This issue does not allow authentication bypass, privilege escalation, data exposure, or remote code execution on its own. Version 4.80.1 contains a patch. As a workaround, run Fleet behind a trusted reverse proxy or load balancer that overwrites client IP headers.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/fleetdm/fleet/releases/tag/fleet-v4.80.1	Release Notes
https://github.com/fleetdm/fleet/security/advisories/GHSA-j8h8-75h3-jg53	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-14 20:17

Updated : 2026-06-17 10:22

NVD link : CVE-2026-24000

Mitre link : CVE-2026-24000

CVE.ORG link : CVE-2026-24000

JSON object : View

Products Affected

fleetdm

fleet

CWE

CWE-290

Authentication Bypass by Spoofing

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