---
id: CVE-2026-95503
title: >-
  A flaw was found in the Kerberos federation provider of Keycloak, an
  open-source identity and access management solution
summary: >-
  A flaw was found in the Kerberos federation provider of Keycloak, an
  open-source identity and access management solution. When Kerberos password
  authentication is used without SPNEGO, the system fails to verify the identity
  of the Key Di…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-347
vendor: Red Hat
product: keycloak/rhbk-openshift-rhel9
affected:
  - keycloak/rhbk-openshift-rhel9 (all versions)
  - keycloak-services (all versions)
  - rhbk/keycloak-rhel9 (all versions)
  - keycloak-services (all versions)
published: '2026-09-22'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T19:37:36.747'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-95503'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-95503'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2537744'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-95503.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-95503'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-95503'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00192
epssPercentile: 0.07861
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-22T14:35:49.382587Z'
ingestedAt: '2026-09-22T08:00:27.684Z'
---

## Overview

A flaw was found in the Kerberos federation provider of Keycloak, an open-source identity and access management solution. When Kerberos password authentication is used without SPNEGO, the system fails to verify the identity of the Key Distribution Center (KDC) by requesting a server ticket. This allows an attacker on the same network to spoof the KDC and bypass the authentication process, potentially gaining unauthorized access to user accounts.

## 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, Red Hat Single Sign-On 7 · no fix planned: Red Hat Single Sign-On 7, Red Hat Build of Keycloak · updated 2026-09-22 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-95503.json)