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.

Project Subscriptions

Vendors Products
Advanced Cluster Management For Kubernetes Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

History

Fri, 21 Aug 2026 13:30:00 +0000

Type Values Removed Values Added
First Time appeared Redhat advanced Cluster Management For Kubernetes
Vendors & Products Redhat advanced Cluster Management For Kubernetes

Fri, 21 Aug 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Important


Thu, 20 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 20 Aug 2026 18:30:00 +0000

Type Values Removed Values Added
Description 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.
Title Lighthouse: lighthouse: cross-cluster dns spoofing via unvalidated endpointslice and serviceimport ips
First Time appeared Redhat
Redhat acm
Weaknesses CWE-345
CPEs cpe:/a:redhat:acm:2
Vendors & Products Redhat
Redhat acm
References
Metrics cvssV3_1

{'score': 8.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-08-20T18:52:19.463Z

Reserved: 2026-07-27T17:51:24.885Z

Link: CVE-2026-66787

cve-icon Vulnrichment

Updated: 2026-08-20T18:52:14.761Z

cve-icon NVD

Status : Received

Published: 2026-08-20T19:16:58.637

Modified: 2026-08-20T19:16:58.637

Link: CVE-2026-66787

cve-icon Redhat

Severity : Important

Publid Date: 2026-08-20T17:20:00Z

Links: CVE-2026-66787 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-21T13:00:58Z

Weaknesses