{"id":"CVE-2026-9798","aliases":["EUVD-2026-32717","GHSA-q6h7-xxp7-7429"],"status":"published","title":"Keycloak: keycloak: brute-force protection bypass in ciba flow","description":"A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. 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hat","product":"red hat build of keycloak 26.4"},{"vendor":"red hat","product":"red hat build of keycloak 26.4.14"},{"vendor":"red hat","product":"red hat build of keycloak 26.6"},{"vendor":"red hat","product":"red hat build of keycloak 26.6.5"},{"vendor":"redhat","product":"build_of_keycloak"}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:50846","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/errata/RHSA-2026:50847","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/errata/RHSA-2026:50848","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/errata/RHSA-2026:50849","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-9798","tags":["vdb-entry","x_refsource_REDHAT","Mitigation","Vendor Advisory","web"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2482470","tags":["issue-tracking","x_refsource_REDHAT","Issue Tracking","Vendor Advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-9798","tags":["advisory"]},{"url":"https://github.com/keycloak/keycloak/issues/49432","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/pull/49791","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/pull/49903","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/pull/49905","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/commit/11c2695064cd93da1d333df3f69d4a4141e86c29","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/commit/2edc6b112e2dedce63062b89ab3c7ae542e0d9ac","tags":["web"]},{"url":"https://github.com/keycloak/keycloak/commit/a11e3254efc16ae72ce5092b93b9f557a4ba43ae","tags":["web"]},{"url":"https://github.com/advisories/GHSA-q6h7-xxp7-7429"},{"url":"https://github.com/keycloak/keycloak","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-9798","title":"Keycloak: keycloak: brute-force protection bypass in ciba flow","description":"A flaw was found in Keycloak, an open-source identity and access management solution. 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When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.","status":"published","published":"2026-05-28T06:16:29.33Z","modified":"2026-10-26T12:10:00.13Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-305"],"updated_at":"2026-11-02T14:12:20.885865Z"}],"osv":[{"id":"GHSA-q6h7-xxp7-7429","title":"Keycloak has an Authentication Bypass by Primary Weakness","description":"A flaw was found in Keycloak, an open-source identity and access management solution. 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