Vulnerability in Red Hat Build Of Keycloak 26.4
CVE-2026-0707
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (32.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 32.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000
Affected products
- Red Hat Build Of Keycloak 26.4 — versions 26.4.10-1, 26.4-12
- Red Hat Build Of Keycloak 26.4.10
Weakness classification (CWE)
References
- access.redhat.com/errata/RHSA-2026:3947 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:3948 (vendor-advisory)
- access.redhat.com/security/cve/CVE-2026-0707 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- github.com/keycloak/keycloak/issues/49433
Frequently asked questions
- What is CVE-2026-0707?
- CVE-2026-0707 is a medium-severity vulnerability in Red Hat Build Of Keycloak 26.4, classified under CWE-551. CVSS score: 5.3/10. Published 2026-01-08.
- How severe is CVE-2026-0707?
- Medium severity. CVSS v3 base score is 5.3 out of 10.