{"id":"CVE-2026-18569","aliases":["EUVD-2026-52575","GHSA-pcf4-9g97-7cpf"],"status":"published","title":"Keycloak-services: keycloak-services: oidc backchannel logout accepts unsigned forged logout tokens","description":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.","severity":{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00314,"percentile":0.24473,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-347"],"published":"2026-08-04T05:13:08Z","modified":"2026-11-07T11:52:17Z","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-2026-18569","tags":["vdb-entry","x_refsource_REDHAT","Vendor Advisory"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2509755","tags":["issue-tracking","x_refsource_REDHAT","Issue Tracking","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18569"},{"url":"https://github.com/advisories/GHSA-pcf4-9g97-7cpf"}],"sources":{"cve":[{"id":"CVE-2026-18569","title":"Keycloak-services: keycloak-services: oidc backchannel logout accepts unsigned forged logout tokens","description":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.","status":"published","published":"2026-08-04T05:13:08.387Z","modified":"2026-11-07T11:52:17.401Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"cna"}],"cwes":["CWE-347"],"updated_at":"2026-11-07T12:33:58.735172Z"}],"euvd":[{"id":"EUVD-2026-52575","description":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.","status":"published","published":"2026-08-04T05:13:08Z","modified":"2026-11-07T11:52:17Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-07T13:09:26.309624Z"}],"ghsa":[{"id":"GHSA-pcf4-9g97-7cpf","title":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is...","description":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.","status":"published","published":"2026-08-04T06:31:36Z","modified":"2026-11-07T12:32:55Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"cwes":["CWE-347"],"updated_at":"2026-11-07T12:37:15.096654Z"}],"nvd":[{"id":"CVE-2026-18569","description":"A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.","status":"published","published":"2026-08-04T06:16:30.14Z","modified":"2026-11-07T12:17:46.403Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"secondary"}],"cwes":["CWE-347"],"updated_at":"2026-11-07T14:05:28.128747Z"}]}}