FKIE_CVE-2026-16093

Vulnerability from fkie_nvd - Published: 2026-07-17 17:17 - Updated: 2026-09-16 19:17
Severity
5.4 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Summary
Keycloak provides a mechanism called Client Policies to enforce security requirements on clients, such as requiring them to use signed JWTs for authentication. A flaw was discovered where this enforcement can be bypassed. An attacker with valid client credentials can provide a fake, unsigned assertion header that tricks the system into thinking the policy requirements have been met. This allows the attacker to authenticate using simpler methods like a client secret even when the administrator has mandated more secure, signed assertions.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:68277
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:68278
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-16093Vendor Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2501729Issue Tracking, Vendor Advisory
Impacted products
Vendor Product Version
redhat build_of_keycloak -
redhat data_grid 8.0
redhat jboss_enterprise_application_platform_expansion_pack -
redhat single_sign-on 7.0
To clipboard 

{
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          "cpes": [
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          "vendor": "Red Hat",
          "versions": [
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              "versionType": "rpm"
            }
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        },
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          "vendor": "Red Hat"
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  "cveTags": [],
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    }
  ],
  "id": "CVE-2026-16093",
  "lastModified": "2026-09-16T19:17:07.373",
  "metrics": {
    "cvssMetricV31": [
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          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.4,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
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        "impactScore": 2.5,
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          "options": [
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            {
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          "role": "CISA Coordinator",
          "timestamp": "2026-07-21T01:45:36.335145Z",
          "version": "2.0.3"
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  "published": "2026-07-17T17:17:14.133",
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      "url": "https://access.redhat.com/errata/RHSA-2026:68277"
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          "value": "CWE-807"
        }
      ],
      "source": "secalert@redhat.com",
      "type": "Secondary"
    }
  ]
}



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Sightings

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Nomenclature

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