Description
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 5.9EPSS 0.158%Risk 0.6
View source- Published
- 2026-05-28 05:16:40
- Affected versions
- unknown
- Type
- Core software
- Last modified
- 2026-08-05 19:17:49
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N