CVE-2026-9793

A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-9793	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2482460	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

03 Jun 2026, 18:26

Type	Values Removed	Values Added
References	~~() https://access.redhat.com/security/cve/CVE-2026-9793 -~~	() https://access.redhat.com/security/cve/CVE-2026-9793 - Vendor Advisory
References	~~() https://bugzilla.redhat.com/show_bug.cgi?id=2482460 -~~	() https://bugzilla.redhat.com/show_bug.cgi?id=2482460 - Issue Tracking, Vendor Advisory
CPE		cpe:2.3:a:redhat:build_of_keycloak:-::::-:::
First Time		Redhat Redhat build Of Keycloak

28 May 2026, 05:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-28 05:16

Updated : 2026-06-03 18:26

NVD link : CVE-2026-9793

Mitre link : CVE-2026-9793

CVE.ORG link : CVE-2026-9793

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-347

Improper Verification of Cryptographic Signature

{"id": "CVE-2026-9793", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "secalert@redhat.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.9, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.2}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "published": "2026-05-28T05:16:40.697", "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-9793", "tags": ["Vendor Advisory"], "source": "secalert@redhat.com"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2482460", "tags": ["Issue Tracking", "Vendor Advisory"], "source": "secalert@redhat.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "secalert@redhat.com", "description": [{"lang": "en", "value": "CWE-347"}]}], "descriptions": [{"lang": "en", "value": "A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements."}], "lastModified": "2026-06-03T18:26:57.263", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "E5C930CB-4EAD-497B-A44B-D880F2A1F85B"}], "operator": "OR"}]}], "sourceIdentifier": "secalert@redhat.com"}