CVE-2026-0707: Red Hat Build Of Keycloak 26.4

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Red Hat Red Hat Build Of Keycloak 26.4: before 26.4.10-1 (fixed in 26.4.10-1); before 26.4-12 (fixed in 26.4-12)
• Red Hat Red Hat Build Of Keycloak 26.4.10

Published 2026-01-08. Last modified 2026-06-17.