FKIE_CVE-2026-9801

Vulnerability from fkie_nvd - Published: 2026-05-28 06:16 - Updated: 2026-10-26 12:10
Severity
4.9 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Summary
A flaw was found in Keycloak. A remote attacker with high privileges, such as a realm administrator configuring a malicious Lightweight Directory Access Protocol (LDAP) server or an attacker compromising an upstream LDAP server, could exploit this vulnerability. By sending a malformed LDAP password policy response during a password authentication request, the attacker can trigger an OutOfMemoryError. This causes the Keycloak Java Virtual Machine (JVM) to terminate, leading to a denial of service (DoS) for all realms on the affected node.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:25097
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:25098
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:30049
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:30050
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-9801Mitigation, Vendor Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2482473Issue Tracking, Vendor Advisory
Impacted products
Vendor Product Version
redhat build_of_keycloak -
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:26.4::el9"
          ],
          "defaultStatus": "affected",
          "packageName": "rhbk/keycloak-operator-bundle",
          "product": "Red Hat build of Keycloak 26.4",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "26.4.13-1",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:26.4::el9"
          ],
          "defaultStatus": "affected",
          "packageName": "rhbk/keycloak-rhel9",
          "product": "Red Hat build of Keycloak 26.4",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "26.4-19",
              "versionType": "rpm"
            }
          ]
        },
        {
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          "cpes": [
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          ],
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          "packageName": "rhbk/keycloak-rhel9-operator",
          "product": "Red Hat build of Keycloak 26.4",
          "vendor": "Red Hat",
          "versions": [
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              "status": "unaffected",
              "version": "26.4-19",
              "versionType": "rpm"
            }
          ]
        },
        {
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          "cpes": [
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          ],
          "defaultStatus": "unaffected",
          "packageName": "rhbk/keycloak-rhel9",
          "product": "Red Hat build of Keycloak 26.4.13",
          "vendor": "Red Hat"
        },
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          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "rhbk/keycloak-operator-bundle",
          "product": "Red Hat build of Keycloak 26.6",
          "vendor": "Red Hat",
          "versions": [
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              "status": "unaffected",
              "version": "26.6.3-3",
              "versionType": "rpm"
            }
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        },
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          ],
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          "packageName": "rhbk/keycloak-rhel9",
          "product": "Red Hat build of Keycloak 26.6",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "26.6-6",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://catalog.redhat.com/software/containers/",
          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "rhbk/keycloak-rhel9-operator",
          "product": "Red Hat build of Keycloak 26.6",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "26.6-6",
              "versionType": "rpm"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:26.6::el9"
          ],
          "defaultStatus": "unaffected",
          "packageName": "rhbk/keycloak-rhel9",
          "product": "Red Hat build of Keycloak 26.6.3",
          "vendor": "Red Hat"
        }
      ],
      "source": "secalert@redhat.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
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              "criteria": "cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*",
              "matchCriteriaId": "E5C930CB-4EAD-497B-A44B-D880F2A1F85B",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
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      ]
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in Keycloak. A remote attacker with high privileges, such as a realm administrator configuring a malicious Lightweight Directory Access Protocol (LDAP) server or an attacker compromising an upstream LDAP server, could exploit this vulnerability. By sending a malformed LDAP password policy response during a password authentication request, the attacker can trigger an OutOfMemoryError. This causes the Keycloak Java Virtual Machine (JVM) to terminate, leading to a denial of service (DoS) for all realms on the affected node."
    },
    {
      "lang": "es",
      "value": "Se encontr\u00f3 un fallo en Keycloak. Un atacante remoto con altos privilegios, como un administrador de reino configurando un servidor malicioso de Lightweight Directory Access Protocol (LDAP) o un atacante comprometiendo un servidor LDAP ascendente, podr\u00eda explotar esta vulnerabilidad. Al enviar una respuesta malformada de pol\u00edtica de contrase\u00f1as LDAP durante una solicitud de autenticaci\u00f3n de contrase\u00f1a, el atacante puede desencadenar un OutOfMemoryError. Esto provoca que la M\u00e1quina Virtual Java (JVM) de Keycloak termine, lo que lleva a una denegaci\u00f3n de servicio (DoS) para todos los reinos en el nodo afectado."
    }
  ],
  "id": "CVE-2026-9801",
  "lastModified": "2026-10-26T12:10:00.130",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 4.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.2,
        "impactScore": 3.6,
        "source": "secalert@redhat.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-9801",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-30T01:53:56.832854Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-28T06:16:29.493",
  "references": [
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:25097"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:25098"
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    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:30049"
    },
    {
      "source": "secalert@redhat.com",
      "url": "https://access.redhat.com/errata/RHSA-2026:30050"
    },
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      "tags": [
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      "url": "https://access.redhat.com/security/cve/CVE-2026-9801"
    },
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      "tags": [
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      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2482473"
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  "sourceIdentifier": "secalert@redhat.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1284"
        }
      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    }
  ]
}



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