CVE-2026-1035

LOW

Keycloak - Refresh Token Reuse Bypass via Non-Atomic Validation in TokenManager

Title source: llm
STIX 2.1

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.

References (4)

Core 4
Core References
Vendor Advisory vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-1035
Issue Tracking issue-tracking x_refsource_redhat
https://bugzilla.redhat.com/show_bug.cgi?id=2430314
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:6477
https://access.redhat.com/errata/RHSA-2026:6477
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:6478
https://access.redhat.com/errata/RHSA-2026:6478

Scores

CVSS v3 3.1
EPSS 0.0028
EPSS Percentile 19.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-367
Status published
Products (8)
org.keycloak/keycloak-services 0Maven
Red Hat/Red Hat Build of Keycloak
Red Hat/Red Hat build of Keycloak 26.4 26.4-14
Red Hat/Red Hat build of Keycloak 26.4 26.4.11-1
Red Hat/Red Hat build of Keycloak 26.4.11
Red Hat/Red Hat JBoss Enterprise Application Platform 8
Red Hat/Red Hat JBoss Enterprise Application Platform Expansion Pack
Red Hat/Red Hat Single Sign-On 7
Published Jan 21, 2026
Tracked Since Feb 18, 2026