CVE-2026-4634

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"rhbk/keycloak-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:red_hat_single_sign_on:7.6"], "vendor": "Red Hat", "product": "Red Hat Single Sign-On 7.6.13", "packageName": "keycloak-services", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:red_hat_single_sign_on:7.6::el7"], "vendor": "Red Hat", "product": "Red Hat Single Sign-On 7.6 for RHEL 7", "versions": [{"status": "unaffected", "version": "0:18.0.20-1.redhat_00001.1.el7sso", "lessThan": "*", "versionType": "rpm"}], "packageName": "rh-sso7-keycloak", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:red_hat_single_sign_on:7.6::el8"], "vendor": "Red Hat", "product": "Red Hat Single Sign-On 7.6 for RHEL 8", "versions": [{"status": "unaffected", "version": 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{"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "affectedData": [{"cpes": ["cpe:/a:redhat:build_keycloak:26.2::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.2", "versions": [{"status": "unaffected", "version": "26.2.15-1", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-operator-bundle", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.2::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.2", "versions": [{"status": "unaffected", "version": "26.2-18", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-rhel9", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.2::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.2", "versions": [{"status": "unaffected", "version": "26.2-18", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-rhel9-operator", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.2::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.2.15", "packageName": "rhbk/keycloak-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.4::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.4", "versions": [{"status": "unaffected", "version": "26.4.11-1", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-operator-bundle", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.4::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.4", "versions": [{"status": "unaffected", "version": "26.4-14", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-rhel9", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.4::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.4", "versions": [{"status": "unaffected", "version": "26.4-14", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhbk/keycloak-rhel9-operator", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:build_keycloak:26.4::el9"], "vendor": "Red Hat", "product": "Red Hat build of Keycloak 26.4.11", "packageName": "rhbk/keycloak-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}]}], "published": "2026-04-02T13:16:27.027", "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:6475", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6476", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6477", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6478", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:76128", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:76129", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:76130", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:76132", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:76134", "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4634", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450250", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6475", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6476", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6477", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6478", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4634", "tags": ["Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450250", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4634.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "secalert@redhat.com", "description": [{"lang": "en", "value": "CWE-1050"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-1050"}]}], "descriptions": [{"lang": "en", "value": "A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the OpenID Connect (OIDC) token endpoint. This leads to high resource consumption and prolonged processing times, ultimately resulting in a Denial of Service (DoS) for the Keycloak server."}, {"lang": "es", "value": "Se encontr\u00f3 un defecto en Keycloak. Un atacante no autenticado puede explotar esta vulnerabilidad enviando una solicitud POST especialmente dise\u00f1ada con un par\u00e1metro \u2019scope\u2019 excesivamente largo al endpoint de token de OpenID Connect (OIDC). Esto conduce a un alto consumo de recursos y tiempos de procesamiento prolongados, lo que finalmente resulta en una denegaci\u00f3n de servicio (DoS) para el servidor Keycloak."}], "lastModified": "2026-10-26T21:10:00.170", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:text-only:*:*:*", "vulnerable": true, "matchCriteriaId": "1830E455-7E11-4264-862D-05971A42D4A6"}, {"criteria": "cpe:2.3:a:redhat:build_of_keycloak:26.2:*:*:*:text-only:*:*:*", "vulnerable": true, "matchCriteriaId": "C339EBE3-6BFD-4082-B904-4E8DB87AAE68"}, {"criteria": "cpe:2.3:a:redhat:build_of_keycloak:26.2.15:*:*:*:text-only:*:*:*", "vulnerable": true, "matchCriteriaId": "3BDF8A92-727E-401B-80BB-A141DCB39750"}, {"criteria": "cpe:2.3:a:redhat:build_of_keycloak:26.4:*:*:*:text-only:*:*:*", "vulnerable": true, "matchCriteriaId": "100AA077-7467-4F62-A8FD-88BC336972DF"}, {"criteria": "cpe:2.3:a:redhat:build_of_keycloak:26.4.11:*:*:*:text-only:*:*:*", "vulnerable": true, "matchCriteriaId": "17E79930-BE1C-4901-AF63-36B3EB149AFC"}], "operator": "OR"}]}], "sourceIdentifier": "secalert@redhat.com"}