A flaw was found in the token sanitization logic of Keycloak, an open source identity and access management solution. The issue occurs when a protocol mapper is configured to emit structured claims using the JSON type. The security check designed to remove unauthorized role mappings only looks for standard Java maps and fails to recognize Jackson based JSON objects. This allows an attacker to inject forged client roles into security tokens, which could lead to unauthorized access to protected resources.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 06 Nov 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A flaw was found in the token sanitization logic of Keycloak, an open source identity and access management solution. The issue occurs when a protocol mapper is configured to emit structured claims using the JSON type. The security check designed to remove unauthorized role mappings only looks for standard Java maps and fails to recognize Jackson based JSON objects. This allows an attacker to inject forged client roles into security tokens, which could lead to unauthorized access to protected resources. | |
| Title | keycloak-services: keycloak-services: Protocol mapper with jsonType=JSON bypasses token sanitization | |
| Weaknesses | CWE-20 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Projects
Sign in to view the affected projects.
No data.
No data.
No data.
OpenCVE Enrichment
No data.
Weaknesses