---
id: CVE-2026-66787
title: >-
  A flaw was found in the lighthouse component of Red Hat Advanced Cluster
  Management for Kubernetes
summary: >-
  A flaw was found in the lighthouse component of Red Hat Advanced Cluster
  Management for Kubernetes. This vulnerability stems from insufficient
  validation of advertised IP addresses within EndpointSlice objects. A
  compromised spoke cluste…
severity: high
cvss: 8.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N'
cwe:
  - CWE-345
published: '2026-08-20'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T22:17:05.020'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-66787'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:63016'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-66787'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2507532'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.00354
epssPercentile: 0.27149
ingestedAt: '2026-10-12T23:07:25.620Z'
---

## Overview

A flaw was found in the lighthouse component of Red Hat Advanced Cluster Management for Kubernetes. This vulnerability stems from insufficient validation of advertised IP addresses within EndpointSlice objects. A compromised spoke cluster can exploit this by creating EndpointSlices with attacker-controlled IP addresses, causing other clusters' lighthouse DNS to redirect legitimate service traffic to malicious endpoints. This enables a remote attacker to conduct transparent Man-in-the-Middle (MITM) attacks on cross-cluster service communications, potentially leading to unauthorized information disclosure and data manipulation.

## Remediation

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