CVE-2026-21891

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{"affected": [{"affectedData": [{"product": "ZimaOS", "vendor": "IceWhaleTech", "versions": [{"status": "affected", "version": "<= 1.5.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:zimaspace:zimaos:*:*:*:*:*:*:*:*", "matchCriteriaId": "F96E7421-2784-4C1C-9785-E4E26C728760", "versionEndIncluding": "1.5.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "ZimaOS is a fork of CasaOS, an operating system for Zima devices and x86-64 systems with UEFI. In versions up to and including 1.5.0, the application checks the validity of the username but appears to skip, misinterpret, or incorrectly validate the password when the provided username matches a known system service account. The application's login function fails to properly handle the password validation result for these users, effectively granting authenticated access to anyone who knows one of these common usernames and provides any password. As of time of publication, no known patched versions are available."}, {"lang": "es", "value": "ZimaOS es un fork de CasaOS, un sistema operativo para dispositivos Zima y sistemas x86-64 con UEFI. En versiones hasta la 1.5.0 inclusive, la aplicaci\u00f3n verifica la validez del nombre de usuario, pero parece omitir, malinterpretar o validar incorrectamente la contrase\u00f1a cuando el nombre de usuario proporcionado coincide con una cuenta de servicio de sistema conocida. La funci\u00f3n de inicio de sesi\u00f3n de la aplicaci\u00f3n no maneja correctamente el resultado de la validaci\u00f3n de la contrase\u00f1a para estos usuarios, otorgando efectivamente acceso autenticado a cualquiera que conozca uno de estos nombres de usuario comunes y proporcione cualquier contrase\u00f1a. A la fecha de publicaci\u00f3n, no hay versiones parcheadas conocidas disponibles."}], "id": "CVE-2026-21891", "lastModified": "2026-06-17T10:19:05.990", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 9.4, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.5, "source": "security-advisories@github.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-21891", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-01-08T14:52:27.926997Z", "version": "2.0.3"}}]}, "published": "2026-01-08T14:15:57.403", "references": [{"source": "security-advisories@github.com", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/IceWhaleTech/ZimaOS/security/advisories/GHSA-xj93-qw9p-jxq4"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/IceWhaleTech/ZimaOS/security/advisories/GHSA-xj93-qw9p-jxq4"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-287"}], "source": "security-advisories@github.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{}

{"created": "2026-01-12T14:38:21.255633+00:00", "updated": "2026-06-18T06:15:14.162284+00:00", "vendors": ["icewhaletech", "icewhaletech$PRODUCT$zimaos"]}