CVE-2026-23998

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{"affected": [{"affectedData": [{"product": "fleet", "vendor": "fleetdm", "versions": [{"status": "affected", "version": "< 4.81.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*", "matchCriteriaId": "84AB2C74-C556-4B42-9A54-A5B201D1BDC3", "versionEndExcluding": "4.81.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Fleet is open source device management software. Prior to version 4.81.0, a vulnerability in Fleet\u2019s 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\u2019s 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 gesti\u00f3n de dispositivos de c\u00f3digo abierto. Antes de la versi\u00f3n 4.81.0, una vulnerabilidad en el endpoint de gesti\u00f3n MDM de Windows de Fleet podr\u00eda permitir que las solicitudes se procesaran sin la validaci\u00f3n adecuada del certificado del cliente. En ciertas circunstancias, esto podr\u00eda permitir a un atacante suplantar la identidad de un dispositivo Windows registrado y recuperar datos de configuraci\u00f3n sensibles. El endpoint de gesti\u00f3n 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 podr\u00edan ser tratadas incorrectamente como de confianza. Como resultado, un atacante con conocimiento previo de un identificador de dispositivo registrado v\u00e1lido podr\u00eda potencialmente suplantar la identidad de ese dispositivo y recibir cargas \u00fatiles de configuraci\u00f3n destinadas a \u00e9l. Estas cargas \u00fatiles pueden contener informaci\u00f3n sensible como datos de configuraci\u00f3n de Wi-Fi o VPN, certificados u otros secretos entregados a trav\u00e9s 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 versi\u00f3n 4.81.0 contiene un parche. Si una actualizaci\u00f3n inmediata no es posible, los usuarios afectados de Fleet deber\u00edan deshabilitar temporalmente el MDM de Windows."}], "id": "CVE-2026-23998", "lastModified": "2026-10-26T14:10:00.130", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "HIGH", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.2, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-23998", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-15T14:12:42.598363Z", "version": "2.0.3"}}]}, "published": "2026-05-14T19:16:30.983", "references": [{"source": "security-advisories@github.com", "tags": ["Product", "Release Notes"], "url": "https://github.com/fleetdm/fleet/releases/tag/fleet-v4.81.0"}, {"source": "security-advisories@github.com", "tags": ["Mitigation", "Vendor Advisory"], "url": "https://github.com/fleetdm/fleet/security/advisories/GHSA-2rc4-7jc6-qffh"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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