Description
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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4 | — | — |
| Red Hat | Red Hat build of Keycloak 26.4.10 | — | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.keycloak:keycloak-parent | <= 26.5.0 | — | GHSA-gv94-wp4h-vv8p |
Advisories 1
- WID-SEC-2026-0034 Keycloak: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Jun 4, 2026
References
- RHSA-2026:3947 vendor-advisory
- RHSA-2026:3948 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-0707 vdb-entry
- RHBZ#2427768 issue-tracking
- https://github.com/keycloak/keycloak/issues/49433