---
id: CVE-2026-15573
title: A flaw was found in Keycloak's Authorization Services
summary: >-
  A flaw was found in Keycloak's Authorization Services. The component
  responsible for matching request paths to security policies (PathMatcher) does
  not properly normalize URIs before comparison. By adding extra characters like
  a trailing…
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-551
  - CWE-178
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: '2026-08-31'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-15573'
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-2026-15573'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2499593'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.00459
epssPercentile: 0.37046
ingestedAt: '2026-08-31T11:07:14.272Z'
---

## Overview

A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing slash or matrix parameters to a URL, an attacker can trick the system into applying a less restrictive security policy than intended. This allows an authenticated user to access administrative or restricted areas they should not have permission to see.

## 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`