CVE-2026-18208 (GCVE-0-2026-18208)
Vulnerability from cvelistv5 – Published: 2026-07-31 07:08 – Updated: 2026-07-31 19:32
VLAI
EPSS
VEX
Title
Keycloak-services: keycloak-services: inactive out-of-audience token introspection leaks signed jwt claim
Summary
A flaw was found in the OIDC token introspection endpoint of the keycloak-services component. Keycloak is an open-source identity and access management solution used to secure modern applications and services. The issue occurs when a confidential client, configured to receive signed JWT introspection responses, attempts to introspect a token issued for a different audience. Although the endpoint correctly identifies the token as inactive for that client, it still returns the full set of token claims within a signed JWT field. This allows an unauthorized client to bypass audience-based restrictions and access sensitive information contained in the token.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-862 - Missing Authorization
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-18208 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2508304 | issue-trackingx_refsource_REDHAT |
Impacted products
4 products
| Vendor | Product | Version | |
|---|---|---|---|
| Red Hat | Red Hat Build of Keycloak |
cpe:/a:redhat:build_keycloak: |
|
| Red Hat | Red Hat Data Grid 8 |
cpe:/a:redhat:jboss_data_grid:8 |
|
| Red Hat | Red Hat JBoss Enterprise Application Platform Expansion Pack |
cpe:/a:redhat:jbosseapxp |
|
| Red Hat | Red Hat Single Sign-On 7 |
cpe:/a:redhat:red_hat_single_sign_on:7 |
Date Public
2026-07-28 13:29
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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