{"id":"CVE-2026-23998","sourceIdentifier":"security-advisories@github.com","published":"2026-05-14T19:16:30.983","lastModified":"2026-10-26T14:10:00.130","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Fleet is open source device management software. Prior to version 4.81.0, a vulnerability in Fleet’s Windows MDM management endpoint could allow requests to be processed without proper client certificate validation. In certain circumstances, this could allow an attacker to impersonate an enrolled Windows device and retrieve sensitive configuration data. Fleet’s Windows MDM management endpoint relies on mutual TLS (mTLS) client certificates to authenticate enrolled devices. In affected versions, requests that did not present a client certificate could be incorrectly treated as trusted. As a result, an attacker with prior knowledge of a valid enrolled device identifier could potentially impersonate that device and receive configuration payloads intended for it. These payloads may contain sensitive information such as Wi-Fi or VPN configuration data, certificates, or other secrets delivered through MDM profiles. This issue does not allow enrollment of new devices, administrative access to Fleet, or compromise of the Fleet control plane. Impact is limited to the targeted Windows device. Version 4.81.0 contains a patch. If an immediate upgrade is not possible, affected Fleet users should temporarily disable Windows MDM."},{"lang":"es","value":"Fleet es un software de gestión de dispositivos de código abierto. Antes de la versión 4.81.0, una vulnerabilidad en el endpoint de gestión MDM de Windows de Fleet podría permitir que las solicitudes se procesaran sin la validación adecuada del certificado del cliente. En ciertas circunstancias, esto podría permitir a un atacante suplantar la identidad de un dispositivo Windows registrado y recuperar datos de configuración sensibles. El endpoint de gestión MDM de Windows de Fleet se basa en certificados de cliente TLS mutuo (mTLS) para autenticar dispositivos registrados. En las versiones afectadas, las solicitudes que no presentaban un certificado de cliente podrían ser tratadas incorrectamente como de confianza. Como resultado, un atacante con conocimiento previo de un identificador de dispositivo registrado válido podría potencialmente suplantar la identidad de ese dispositivo y recibir cargas útiles de configuración destinadas a él. Estas cargas útiles pueden contener información sensible como datos de configuración de Wi-Fi o VPN, certificados u otros secretos entregados a través de perfiles MDM. Este problema no permite el registro de nuevos dispositivos, el acceso administrativo a Fleet, o el compromiso del plano de control de Fleet. El impacto se limita al dispositivo Windows objetivo. La versión 4.81.0 contiene un parche. Si una actualización inmediata no es posible, los usuarios afectados de Fleet deberían deshabilitar temporalmente el MDM de Windows."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"fleetdm","product":"fleet","versions":[{"version":"< 4.81.0","status":"affected"}]}]}],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":8.2,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"NONE"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-05-15T14:12:42.598363Z","id":"CVE-2026-23998","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-295"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*","versionEndExcluding":"4.81.0","matchCriteriaId":"84AB2C74-C556-4B42-9A54-A5B201D1BDC3"}]}]}],"references":[{"url":"https://github.com/fleetdm/fleet/releases/tag/fleet-v4.81.0","source":"security-advisories@github.com","tags":["Product","Release Notes"]},{"url":"https://github.com/fleetdm/fleet/security/advisories/GHSA-2rc4-7jc6-qffh","source":"security-advisories@github.com","tags":["Mitigation","Vendor Advisory"]}]}