PatchSiren cyber security CVE debrief
CVE-2026-0707 Red Hat CVE debrief
CVE-2026-0707 is a medium-severity vulnerability in Keycloak, a popular open-source identity and access management solution. The vulnerability, with a CVSS score of 5.3, stems from the Keycloak Authorization header parser being overly permissive regarding the formatting of the 'Bearer' authentication scheme. Specifically, it accepts non-standard characters (such as tabs) as separators and tolerates case variations that deviate from RFC 6750 specifications. This could potentially lead to security issues, although no specific attack scenarios have been detailed.
- Vendor
- Red Hat
- Product
- Red Hat build of Keycloak 26.4
- CVSS
- MEDIUM 5.3
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-01-08
- Original CVE updated
- 2026-06-08
- Advisory published
- 2026-01-08
- Advisory updated
- 2026-06-08
Who should care
Security teams and administrators responsible for Keycloak deployments should be aware of this vulnerability. Given its medium severity, it may not require immediate action but should be evaluated and patched according to the organization's risk management policies.
Technical summary
The Keycloak Authorization header parser does not strictly adhere to RFC 6750 specifications for the 'Bearer' authentication scheme. It allows for non-standard characters as separators and is case-insensitive, which could lead to potential security issues if exploited.
Defensive priority
Medium
Recommended defensive actions
- Apply patches or updates provided by the Keycloak maintainers or relevant vendors (e.g., Red Hat) as they become available.
- Review and adjust Keycloak configurations to align with RFC 6750 specifications if possible.
- Monitor Keycloak deployments for any suspicious activity related to authentication headers.
Evidence notes
The CVE was published on January 8, 2026, and modified on June 8, 2026. Multiple references are provided, including links to Red Hat errata and a Keycloak GitHub issue.
Sources and references
Verified primary and authoritative sources
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CVE-2026-0707 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-0707
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-0707 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-0707
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
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Source reference
Unverified legacy reference
URL: https://access.redhat.com/errata/RHSA-2026:3947
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Source reference
Unverified legacy reference
URL: https://access.redhat.com/errata/RHSA-2026:3948
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Source reference
Unverified legacy reference
URL: https://access.redhat.com/security/cve/CVE-2026-0707
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Source reference
Unverified legacy reference
URL: https://github.com/keycloak/keycloak/issues/49433
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.