{"id":"CVE-2026-1035","aliases":["EUVD-2026-3691","GHSA-m2w5-7xhv-w6fh","UBUNTU-CVE-2026-1035"],"status":"published","title":"Org.keycloak.protocol.oidc: keycloak refresh token reuse bypass via toctou race condition","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. 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hat","product":"red hat build of keycloak 26.4"},{"vendor":"red hat","product":"red hat build of keycloak 26.4.11"},{"vendor":"red hat","product":"red hat jboss enterprise application platform 8"},{"vendor":"red hat","product":"red hat jboss enterprise application platform expansion pack"},{"vendor":"red hat","product":"red hat single sign-on 7"}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:6477","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/errata/RHSA-2026:6478","tags":["vendor-advisory","x_refsource_REDHAT","web"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-1035","tags":["vdb-entry","x_refsource_REDHAT","web","report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2430314","tags":["issue-tracking","x_refsource_REDHAT","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-1035","tags":["advisory"]},{"url":"https://github.com/keycloak/keycloak/issues/45647","tags":["web"]},{"url":"https://github.com/advisories/GHSA-m2w5-7xhv-w6fh"},{"url":"https://github.com/keycloak/keycloak","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-1035","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-1035","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-1035","title":"Org.keycloak.protocol.oidc: keycloak refresh token reuse bypass via toctou race condition","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T05:52:22.495Z","modified":"2026-04-02T16:47:18.487Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"cna"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:20:00.879257Z"}],"euvd":[{"id":"EUVD-2026-3691","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T05:52:22Z","modified":"2026-04-02T16:47:18Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T19:25:22.606516Z"}],"ghsa":[{"id":"GHSA-m2w5-7xhv-w6fh","title":"Keycloak does not validate and update refresh token usage atomically","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T06:31:20Z","modified":"2026-04-02T15:31:35Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:39:47.945242Z"}],"nvd":[{"id":"CVE-2026-1035","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T06:15:46.937Z","modified":"2026-06-17T10:14:53.58Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:12:04.423757Z"}],"osv":[{"id":"GHSA-m2w5-7xhv-w6fh","title":"Keycloak does not validate and update refresh token usage atomically","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T06:31:20Z","modified":"2026-04-02T15:46:52.447899Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T15:46:51.10002Z"},{"id":"UBUNTU-CVE-2026-1035","description":"A flaw was found in the Keycloak server during refresh token processing, specifically in the TokenManager class responsible for enforcing refresh token reuse policies. When strict refresh token rotation is enabled, the validation and update of refresh token usage are not performed atomically. This allows concurrent refresh requests to bypass single-use enforcement and issue multiple access tokens from the same refresh token. As a result, Keycloak’s refresh token rotation hardening can be undermined.","status":"published","published":"2026-01-21T06:15:00Z","modified":"2026-10-17T12:57:58.196718335Z","cvss":[{"version":"3.1","score":3.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T16:55:59.130573Z"}]}}