---
id: CVE-2026-16102
title: >-
  A flaw was found in the Dynamic Client Registration (DCR) component of
  Keycloak, an identity and access management solution
summary: >-
  A flaw was found in the Dynamic Client Registration (DCR) component of
  Keycloak, an identity and access management solution. The default DCR policy
  fails to properly validate the claim path for User Property mappers, allowing
  them to wri…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-284
vendor: redhat
product: build_of_keycloak
affected:
  - 'build_of_keycloak >= 26.4, < 26.4.14'
  - 'build_of_keycloak >= 26.6, < 26.6.5'
  - data_grid = 8.0
  - jboss_enterprise_application_platform_expansion_pack
  - single_sign-on = 7.0
patched:
  - build_of_keycloak 26.6.5
published: '2026-08-05'
updated: '2026-08-21'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-16102'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:50846'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50847'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50848'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50849'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-16102'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2501735'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.00459
epssPercentile: 0.37046
ingestedAt: '2026-08-22T13:32:35.809Z'
---

## Overview

A flaw was found in the Dynamic Client Registration (DCR) component of Keycloak, an identity and access management solution. The default DCR policy fails to properly validate the claim path for User Property mappers, allowing them to write values to sensitive internal claim locations. An attacker with a standard user account and a limited Initial Access Token can exploit this to forge administrative roles in their access token. This allows the attacker to take over other clients, steal confidential secrets, and potentially gain full administrative control over the realm.

## Affected

- `build_of_keycloak >= 26.4, < 26.4.14`
- `build_of_keycloak >= 26.6, < 26.6.5`
- `data_grid = 8.0`
- `jboss_enterprise_application_platform_expansion_pack`
- `single_sign-on = 7.0`

## Remediation

Upgrade past the affected range:

- `build_of_keycloak 26.6.5`