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CVE-2026-8204

Estado: AnalizadaMedia (6.3)—

Concrete CMS 9.5.0 and below is vulnerable to authorization Bypass in the Calendar Event Frontend Dialog which can allow cross-calendar data disclosure. A public calendar block can be used as a pivot point to access private calendar data. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Concretecms — Concrete CMS

CWE

Referencias

JSON original (NVD)

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          "version": "2.0.3",
          "timestamp": "2026-05-22T12:27:29.187587Z"
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          "integrityImpact": "NONE",
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    "cvssMetricV40": [
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        "type": "Secondary",
        "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
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          "valueDensity": "NOT_DEFINED",
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          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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              "version": "5",
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  "published": "2026-05-21T21:16:33.530",
  "references": [
    {
      "url": "https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes",
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        "Release Notes"
      ],
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  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
      "description": [
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          "value": "CWE-639"
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  ],
  "descriptions": [
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      "lang": "en",
      "value": "Concrete CMS 9.5.0 and below is vulnerable to authorization Bypass in the Calendar Event Frontend Dialog which can allow cross-calendar data disclosure. A public calendar block can be used as a pivot point to access private calendar data. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting."
    },
    {
      "lang": "es",
      "value": "Concrete CMS 9.5.0 y versiones anteriores es vulnerable a una omisión de autorización en el Diálogo Frontend de Eventos del Calendario, lo que puede permitir la divulgación de datos entre calendarios. Un bloque de calendario público puede ser utilizado como punto de pivote para acceder a datos de calendario privados. El equipo de seguridad de Concrete CMS otorgó a esta vulnerabilidad una puntuación CVSS v.4.0 de 6.3 con el vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Gracias a Winston Crooker por informar."
    }
  ],
  "lastModified": "2026-07-23T16:10:00.137",
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          "negate": false,
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