{"cve":"CVE-2026-1035","nvd":{"published":"2026-01-21T06:15:46.937","modified":"2026-06-17T10:14:53.580","status":"Deferred","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","score":3.1},"cwes":["CWE-367"],"references":["https://access.redhat.com/errata/RHSA-2026:6477","https://access.redhat.com/errata/RHSA-2026:6478","https://access.redhat.com/security/cve/CVE-2026-1035","https://bugzilla.redhat.com/show_bug.cgi?id=2430314"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:21:16.563232421+00:00"},"epss":{"cve":"CVE-2026-1035","score":0.00303,"percentile":0.23146,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-m2w5-7xhv-w6fh","url":"https://osv.dev/vulnerability/GHSA-m2w5-7xhv-w6fh","summary":"Keycloak does not validate and update refresh token usage atomically","modified":"2026-04-02T15:46:52.447899Z","packages":[{"ecosystem":"Maven","name":"org.keycloak:keycloak-services","purl":"pkg:maven/org.keycloak/keycloak-services","ranges":["<=26.2.5"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}