CVE-2026-1035 (GCVE-0-2026-1035)

Vulnerability from cvelistv5 – Published: 2026-01-21 05:52 – Updated: 2026-04-02 16:47
VLAI?
Title
Org.keycloak.protocol.oidc: keycloak refresh token reuse bypass via toctou race condition
Summary
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.
Severity ?
3.1 (Low)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
https://access.redhat.com/errata/RHSA-2026:6477 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6478 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-1035 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2430314 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.11-1 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat build of Keycloak 26.4.11     cpe:/a:redhat:build_keycloak:26.4::el9
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    Red Hat Red Hat JBoss Enterprise Application Platform 8     cpe:/a:redhat:jboss_enterprise_application_platform:8
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    Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack     cpe:/a:redhat:jbosseapxp
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    Red Hat Red Hat Single Sign-On 7     cpe:/a:redhat:red_hat_single_sign_on:7
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Date Public ?
2026-01-21 00:00
Credits
Red Hat would like to thank Mohamed Amine ait Ouchebou (mrecho) (Indiesecurity) for reporting this issue.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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