---
id: CVE-2026-105306
title: >-
  A flaw was found in the Dynamic Client Registration flow of the Keycloak
  identity and access management server
summary: >-
  A flaw was found in the Dynamic Client Registration flow of the Keycloak
  identity and access management server. The issue occurs because the
  registration process fails to filter security-sensitive client attributes when
  a new client is c…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-862
vendor: Red Hat
product: keycloak-services
affected:
  - keycloak-services (all versions)
  - rhbk/keycloak-rhel9 (all versions)
  - keycloak-services
published: '2026-10-05'
updated: '2026-10-05'
sourceUpdated: '2026-10-05T06:16:58.530'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-105306'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-105306'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2545802'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-105306.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-105306'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-105306'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-10-05T06:13:49.200Z'
---

## Overview

A flaw was found in the Dynamic Client Registration flow of the Keycloak identity and access management server. The issue occurs because the registration process fails to filter security-sensitive client attributes when a new client is created. An attacker with a valid Initial Access Token can register a client that bypasses audience checks during token introspection. This allows the attacker to view sensitive identity information, roles, and session details from access tokens belonging to other applications in the same realm.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Build of Keycloak · no fix planned: Red Hat Build of Keycloak · updated 2026-10-05 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-105306.json)