{"id":"CVE-2026-16103","aliases":["EUVD-2026-45225","GHSA-v7m3-vpqr-6m6p"],"status":"published","title":"Keycloak-services: keycloak-services: incomplete fix for ciba brute-force lockout bypass at token redemption","description":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.","severity":{"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":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00437,"percentile":0.38276,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-305","CWE-841"],"published":"2026-07-17T16:43:50Z","modified":"2026-11-06T17:34:04Z","products":[{"vendor":"red hat","product":"red hat build of keycloak 26.6"},{"vendor":"red hat","product":"red hat build of keycloak 26.6.8"},{"vendor":"red hat","product":"red hat data grid 8"},{"vendor":"red hat","product":"red hat jboss enterprise application platform expansion pack"},{"vendor":"red hat","product":"red hat single sign-on 7"},{"vendor":"redhat","product":"build_of_keycloak"}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:95761","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:95762","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-16103","tags":["vdb-entry","x_refsource_REDHAT","Vendor Advisory"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2501736","tags":["issue-tracking","x_refsource_REDHAT","Issue Tracking","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-16103"},{"url":"https://github.com/advisories/GHSA-v7m3-vpqr-6m6p"}],"sources":{"cve":[{"id":"CVE-2026-16103","title":"Keycloak-services: keycloak-services: incomplete fix for ciba brute-force lockout bypass at token redemption","description":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.","status":"published","published":"2026-07-17T16:43:50.887Z","modified":"2026-11-06T17:34:04.56Z","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":"cna"}],"cwes":["CWE-305","CWE-841"],"updated_at":"2026-11-06T18:59:08.498645Z"}],"euvd":[{"id":"EUVD-2026-45225","description":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.","status":"published","published":"2026-07-17T16:43:50Z","modified":"2026-11-06T17:34:04Z","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"}],"updated_at":"2026-11-06T18:05:39.47551Z"}],"ghsa":[{"id":"GHSA-v7m3-vpqr-6m6p","title":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix...","description":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.","status":"published","published":"2026-07-17T18:31:26Z","modified":"2026-11-06T18:34:17Z","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"}],"cwes":["CWE-305","CWE-841"],"updated_at":"2026-11-06T19:01:25.944997Z"}],"nvd":[{"id":"CVE-2026-16103","description":"A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.","status":"published","published":"2026-07-17T17:17:14.263Z","modified":"2026-11-06T18:18:08.88Z","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","CWE-841"],"updated_at":"2026-11-06T20:01:12.161832Z"}]}}