---
id: CVE-2026-16108
title: >-
  A flaw was found in the default-groups REST endpoint and realm representation
  of Keycloak
summary: >-
  A flaw was found in the default-groups REST endpoint and realm representation
  of Keycloak. This component is responsible for managing groups that are
  automatically assigned to new users within a realm. The issue allows a
  delegated admini…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-1220
  - CWE-200
vendor: redhat
product: build_of_keycloak
affected:
  - build_of_keycloak
patched:
  - build_of_keycloak 26.6.7
published: '2026-07-17'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:17:07.940'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-16108'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:68277'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:68278'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-16108'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2501740'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-16108.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-16108'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-16108'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.0037
epssPercentile: 0.28187
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-17T17:20:03.634038Z'
ingestedAt: '2026-08-31T11:07:14.084Z'
---

## Overview

A flaw was found in the default-groups REST endpoint and realm representation of Keycloak. This component is responsible for managing groups that are automatically assigned to new users within a realm. The issue allows a delegated administrator with realm-viewing permissions to see the names and identifiers of hidden default groups, even if they lack the specific permissions to view those groups. This can lead to the exposure of sensitive organizational structures or internal group names.

## Affected

- `build_of_keycloak`

## Remediation

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

## Vendor advisories

- **RHSA-2026:68278** · Red Hat · fixed in: Red Hat build of Keycloak 26.6.7 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68278)
- **RHSA-2026:68277** · Red Hat · fixed in: Red Hat build of Keycloak 26.6 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68277)