CVE-2026-1035CWE-367

Org.keycloak.protocol.oidc: keycloak refresh token reuse bypass via toctou race condition

Low · published January 21, 2026

CVSS v3.1
3.1
EPSS
0%
Percentile
21.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
3.1 · LOW
Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00303 · 21.9th percentile
Weakness
CWE-367 · Time-of-check Time-of-use (TOCTOU) Race Condition
Published
2026-01-21T05:52Z
EPSS history
Timeline
  • 21 JAN 05:52Z
    Org.keycloak.protocol.oidc: keycloak refresh token reuse bypass via toctou race condition
    cvelistv5