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CVE-2026-55772

Full vulnerability record from the local CVENow database.

Description

CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. In versions prior to 2.3.6, 3.4.1 and 4.9.0, under certain circumstances, improper input handling could allow Record-to-Entity type confusion across the Java-Rust FFI boundary. CedarJava sends authorization requests to the Rust cedar-policy evaluator as JSON. The JSON protocol reserves magic single-key object shapes (__entity and __extn) for entity references and extension values. When serializing a CedarMap, there is no validation preventing these reserved keys from being used. If an integrating service builds a CedarMap from caller-supplied key/value data (such as request headers, user-defined metadata, or resource tags), an actor who controls those keys could cause the Rust evaluator to interpret a record as an entity reference. This issue requires the integrating service to build a CedarMap where the an actor controls the keys, and a policy must reference that value in a when/unless clause. This vulnerability has been fixed in versions 2.3.6, 3.4.1, and 4.9.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Deferred
Source identifier
Published
2026-07-13 19:17:15.183000
Last modified
2026-10-24 22:10:00.210000
View original CVE JSON
{
  "id": "CVE-2026-55772",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-13T19:17:15.183",
  "lastModified": "2026-10-24T22:10:00.210",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. In versions prior to 2.3.6, 3.4.1 and 4.9.0, under certain circumstances, improper input handling could allow Record-to-Entity type confusion across the Java-Rust FFI boundary. CedarJava sends authorization requests to the Rust cedar-policy evaluator as JSON. The JSON protocol reserves magic single-key object shapes (__entity and __extn) for entity references and extension values. When serializing a CedarMap, there is no validation preventing these reserved keys from being used. If an integrating service builds a CedarMap from caller-supplied key/value data (such as request headers, user-defined metadata, or resource tags), an actor who controls those keys could cause the Rust evaluator to interpret a record as an entity reference. This issue requires the integrating service to build a CedarMap where the an actor controls the keys, and a policy must reference that value in a when/unless clause. This vulnerability has been fixed in versions 2.3.6, 3.4.1, and 4.9."
    },
    {
      "lang": "es",
      "value": "CedarJava es una implementación Java de código abierto del lenguaje de políticas Cedar, utilizada para decisiones de autorización de grano fino. En versiones anteriores a la 2.3.6, 3.4.1 y 4.9.0, bajo ciertas circunstancias, un manejo inadecuado de la entrada podría permitir una confusión de tipo de Registro a Entidad a través del límite FFI de Java-Rust. CedarJava envía solicitudes de autorización al evaluador de políticas Cedar de Rust como JSON. El protocolo JSON reserva formas de objeto mágicas de clave única (__entity y __extn) para referencias de entidad y valores de extensión. Al serializar un CedarMap, no hay validación que impida el uso de estas claves reservadas. Si un servicio integrador construye un CedarMap a partir de datos clave/valor proporcionados por el llamador (como encabezados de solicitud, metadatos definidos por el usuario o etiquetas de recursos), un actor que controle esas claves podría hacer que el evaluador de Rust interprete un registro como una referencia de entidad. Este problema requiere que el servicio integrador construya un CedarMap donde un actor controle las claves, y una política debe hacer referencia a ese valor en una cláusula when/unless. Esta vulnerabilidad ha sido corregida en las versiones 2.3.6, 3.4.1 y 4.9."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "cedar-policy",
          "product": "cedar-java",
          "versions": [
            {
              "version": "< 2.3.6",
              "status": "affected"
            },
            {
              "version": ">= 3.1.2, < 3.4.1",
              "status": "affected"
            },
            {
              "version": ">= 4.0.0, < 4.9.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-21T19:02:38.661180Z",
          "id": "CVE-2026-55772",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-843"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/cedar-policy/cedar-java/security/advisories/GHSA-93g4-m6xv-cmvr",
      "source": "[email protected]"
    }
  ]
}