CVE-2026-24000
mediumpriority · track · 21EPSS 0.004 · 36 %ileDEEUUSEPSS · scored 2026-10-23
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.7–6.9
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (9)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1553Fleet: Mehrere SchwachstellenDeutsch2026-05-14csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Fleet ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder einen Denial-of-Service-Zustand herbeizuführen.
- GHSA-j8h8-75h3-jg53Fleet has a rate limiting bypass via untrusted client IP headers2026-05-14ghsa · osvUS
### Impact 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 - 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. ### Workarounds Run Fleet behind a trusted reverse proxy or load balancer that overwrites client IP headers. ### For more information If you have any questions or comments about this advisory: Email us at [security@fleetdm.com](mailto:security@fleetdm.com) Join #fleet in [osquery Slack](https://join.slack.com/t/osquery/shared_invite/zt-h29zm0gk-s2DBtGUTW4CFel0f0IjTEw) ### Credits We thank @fuzzztf for responsibly reporting this issue.
- GO-2026-5455Fleet has a rate limiting bypass via untrusted client IP headers in github.com/fleetdm/fleet2026-06-25vendor · osvUS
Fleet has a rate limiting bypass via untrusted client IP headers in github.com/fleetdm/fleet
also known as (5)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://github.com/fleetdm/fleet/releases/Patchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-24000cnnvd
- https://github.com/fleetdm/fleet/releases/tag/fleet-v4.80.1enisa_euvd
- https://github.com/fleetdm/fleet/security/advisories/GHSA-j8h8-75h3-jg53enisa_euvd
- https://github.com/fleetdm/fleet/releases/tag/fleet-v4.80.1Release Notesnvd
- https://github.com/fleetdm/fleet/security/advisories/GHSA-j8h8-75h3-jg53Vendor Advisorynvd
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