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CVE-2026-0707 (GCVE-0-2026-0707)

Vulnerability from cvelistv5 – Published: 2026-01-08 03:41 – Updated: 2026-06-08 10:21
VLAI
Title
Keycloak: keycloak authorization header parsing leading to potential security control bypass
Summary
A flaw was found in Keycloak. The Keycloak Authorization header parser is overly permissive regarding the formatting of the "Bearer" authentication scheme. It accepts non-standard characters (such as tabs) as separators and tolerates case variations that deviate from RFC 6750 specifications.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-08 15:54 UTC
CWE
  • CWE-551 - Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
Assigner
References
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.10-1 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-12 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.4.10     cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Date Public
2026-01-07 00:00
Credits
Red Hat would like to thank Guanping Zhang for reporting this issue.
Show details on NVD website
To clipboard 

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