CVE-2026-109081 json
Keycloak-services: keycloak-services: injection of roles into realm default-roles via dcr endpoint
published 3d ago modified 3d ago also EUVD-2026-117893
- cvss
- 6.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
A flaw was found in Keycloak. The Dynamic Client Registration (DCR) endpoint does not properly validate authorization when processing the deprecated defaultRoles field. An authenticated attacker with client creation privileges or an Initial Access Token (IAT) can inject excessive roles into the realm's default roles configuration. This causes clients across the realm to generate bloated access tokens, resulting in performance and memory degradation that can lead to a Denial of Service (DoS).
Patch / fix
- Red Hat Red Hat build of Keycloak 26.6 26.6-24, 26.6.8-2
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red hat product security vex CVE-2026-109081 updated cvss 6.8
keycloak-services: keycloak-services: Injection of roles into realm default-roles via DCR endpoint
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Red Hat build of Keycloak 26.6 rhbk/keycloak-rhel9 26.6-24, rhbk/keycloak-rhel9-operator 26.6-24, rhbk/keycloak-operator-bundle 26.6.8-2fixed: vendor fix RHSA-2026:95762
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Red Hat build of Keycloak 26.6.8fixed: vendor fix RHSA-2026:95761
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Red Hat Single Sign-On 7 keycloak-services 18.0.20.redhat-00001not affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.46% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H |
Affected products
- Red Hat Red Hat build of Keycloak 26.6
- Red Hat Red Hat build of Keycloak 26.6.8
- Red Hat Red Hat Single Sign-On 7
Classification
- Weakness
-
- CWE-862 Missing Authorization
References
-
access.redhat.com
/errata/RHSA-2026:95761
vendor-advisory
-
access.redhat.com
/errata/RHSA-2026:95762
vendor-advisory
-
access.redhat.com
/security/cve/CVE-2026-109081
vdb-entry
Sources
- CVE List CVE-2026-109081
- NVD CVE-2026-109081
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