Vulnerability-Lookup

GHSA-GV94-WP4H-VV8P

Vulnerability from github – Published: 2026-01-08 06:31 – Updated: 2026-06-09 11:58

Summary

Keycloak has Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

Details

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

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.keycloak:keycloak-parent"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
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              "last_affected": "26.5.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-0707"
  ],
  "database_specific": {
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    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-08T21:14:12Z",
    "nvd_published_at": "2026-01-08T04:15:56Z",
    "severity": "MODERATE"
  },
  "details": "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.",
  "id": "GHSA-gv94-wp4h-vv8p",
  "modified": "2026-06-09T11:58:24Z",
  "published": "2026-01-08T06:31:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0707"
    },
    {
      "type": "WEB",
      "url": "https://github.com/keycloak/keycloak/issues/49433"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3947"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3948"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-0707"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2427768"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/keycloak/keycloak"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Keycloak has Incorrect Behavior Order: Authorization Before Parsing and Canonicalization"
}

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

Vulnerability from cvelistv5 – Published: 2026-01-08 03:41 – Updated: 2026-06-08 10:21

Title

Keycloak: keycloak authorization header parsing leading to potential security control bypass

Summary

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

redhat redhat root Scorecard

References

5 references

URL	Tags
https://access.redhat.com/errata/RHSA-2026:3947	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:3948	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-0707	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2427768	issue-trackingx_refsource_REDHAT
https://github.com/keycloak/keycloak/issues/49433

Impacted products

3 products

Vendor	Product	Version
Red Hat	Red Hat build of Keycloak 26.4	Unaffected: 26.4.10-1 , < * (rpm) cpe:/a:redhat:build_keycloak:26.4::el9
Red Hat	Red Hat build of Keycloak 26.4	Unaffected: 26.4-12 , < * (rpm) cpe:/a:redhat:build_keycloak:26.4::el9
Red Hat	Red Hat build of Keycloak 26.4.10	cpe:/a:redhat:build_keycloak:26.4::el9

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

JSON

To clipboard

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                  },
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                  }
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                "timestamp": "2026-01-08T15:54:59.827077Z",
                "version": "2.0.3"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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GHSA-GV94-WP4H-VV8P

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

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