CVE-2026-39857

{
  "id": "CVE-2026-39857",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-15T20:16:36.567",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "ApostropheCMS is an open-source Node.js content management system. Versions 4.28.0 and prior contain an authorization bypass vulnerability in the choices and counts query parameters of the REST API, where these query builders execute MongoDB distinct() operations that bypass the publicApiProjection restrictions intended to limit which fields are exposed publicly. The choices and counts parameters are processed via applyBuildersSafely before the projection is applied, and MongoDB's distinct operation does not respect projections, returning all distinct values directly. The results are returned in the API response without any filtering against publicApiProjection or removeForbiddenFields. An unauthenticated attacker can extract all distinct field values for any schema field type that has a registered query builder, including string, integer, float, select, boolean, date, slug, and relationship fields. Fields protected with viewPermission are similarly exposed, and the counts variant additionally reveals how many documents have each distinct value. Both the piece-type and page REST APIs are affected. This issue has been fixed in version 4.29.0."
    },
    {
      "lang": "es",
      "value": "ApostropheCMS es un sistema de gestión de contenido de código abierto basado en Node.js. Las versiones 4.28.0 y anteriores contienen una vulnerabilidad de omisión de autorización en los parámetros de consulta choices y counts de la API REST, donde estos constructores de consultas ejecutan operaciones MongoDB distinct() que omiten las restricciones de publicApiProjection destinadas a limitar qué campos se exponen públicamente. Los parámetros choices y counts se procesan a través de applyBuildersSafely antes de que se aplique la proyección, y la operación distinct de MongoDB no respeta las proyecciones, devolviendo todos los valores distintos directamente. Los resultados se devuelven en la respuesta de la API sin ningún filtrado contra publicApiProjection o removeForbiddenFields. Un atacante no autenticado puede extraer todos los valores de campo distintos para cualquier tipo de campo de esquema que tenga un constructor de consultas registrado, incluyendo campos de cadena, entero, flotante, selección, booleano, fecha, slug y relación. Los campos protegidos con viewPermission se exponen de manera similar, y la variante counts revela adicionalmente cuántos documentos tienen cada valor distinto. Ambas API REST de tipo pieza y de página se ven afectadas. Este problema ha sido solucionado en la versión 4.29.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "apostrophecms",
          "product": "apostrophe",
          "versions": [
            {
              "version": "< 4.29.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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        "source": "[email protected]",
        "type": "Secondary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
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        "ssvcData": {
          "timestamp": "2026-04-16T13:40:14.273773Z",
          "id": "CVE-2026-39857",
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          "role": "CISA Coordinator",
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-200"
        }
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  "references": [
    {
      "url": "https://github.com/apostrophecms/apostrophe/commit/6c2b548dec2e3f7a82e8e16736603f4cd17525aa",
      "source": "[email protected]",
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