Token claim disclosure via unsanitized introspection response
Published Jul 31, 2026 · Updated Jul 31, 2026
Missing authorization in Red Hat build of Keycloak allows remote authenticated users to read restricted token claims through OIDC introspection. The keycloak-services introspection endpoint marks an out-of-audience token inactive but leaves its full claims in the signed JWT response field. Exploitation requires control of a confidential client configured for signed JWT introspection in the same realm and a valid token for another audience; disclosure is limited to token claims.
Summary
What happened
Missing authorization in Red Hat build of Keycloak allows remote authenticated users to read restricted token claims through OIDC introspection. The keycloak-services introspection endpoint marks an out-of-audience token inactive but leaves its full claims in the signed JWT response field. Exploitation requires control of a confidential client configured for signed JWT introspection in the same realm and a valid token for another audience; disclosure is limited to token claims.
The record
- CVE
- CVE-2026-18208
- Published
- Jul 31, 2026
- Updated
- Jul 31, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat build of Keycloak
- Classifications
- CWE-862
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 31, 2026CVE publishedPublication date reported by the CVE source.
- Jul 31, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
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Your stack
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