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.
Published:May 28, 2026
Last Modified:Aug 5, 2026
EPS:May 28, 2026
EPSS Score:0.0012
CVSS Score:5.9
Affected Products
Vendor
Product
Action
Vendor
Redhat
Product
Build Keycloak
Redhat
Build Keycloak
Vendor
Redhat
Product
Build Of Keycloak
Redhat
Build Of Keycloak
Vendor
Redhat
Product
Keycloak
Redhat
Keycloak
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
References
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
