CVE-2026-37979

{
  "id": "CVE-2026-37979",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-19T12:16:18.330",
  "lastModified": "2026-10-29T10:17:04.177",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials."
    },
    {
      "lang": "es",
      "value": "Se encontró una falla en Keycloak. Esta vulnerabilidad de control de acceso en el endpoint de introspección de tokens de OpenID Connect (OIDC) de Keycloak permite a un cliente confidencial eludir las restricciones de audiencia. Un cliente controlado por un atacante con credenciales válidas puede recuperar claims de token sensibles destinados a otros servidores de recursos, comprometiendo la confidencialidad de los tokens de acceso ligeros. Este problema puede ser explotado remotamente por cualquier cliente confidencial en el realm con credenciales válidas."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Keycloak 26.4",
          "defaultStatus": "affected",
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          "packageName": "rhbk/keycloak-operator-bundle",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:26.4::el9"
          ],
          "versions": [
            {
              "version": "26.4.12-1",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Keycloak 26.4",
          "defaultStatus": "affected",
          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "packageName": "rhbk/keycloak-rhel9",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:26.4::el9"
          ],
          "versions": [
            {
              "version": "26.4-17",
              "lessThan": "*",
              "versionType": "rpm",
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            }
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        },
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          ],
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              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
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          "vendor": "Red Hat",
          "product": "Red Hat build of Keycloak 26.4.12",
          "defaultStatus": "unaffected",
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          "packageName": "rhbk/keycloak-rhel9",
          "cpes": [
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          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6
      }
    ],
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        "ssvcData": {
          "timestamp": "2026-05-19T13:39:36.285295Z",
          "id": "CVE-2026-37979",
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          "role": "CISA Coordinator",
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
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          "value": "CWE-639"
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  "references": [
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:19596",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
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      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
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      "url": "https://access.redhat.com/security/cve/CVE-2026-37979",
      "source": "[email protected]",
      "tags": [
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    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2455328",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
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}