CVE-2026-66787 PUBLISHED

Lighthouse: lighthouse: cross-cluster dns spoofing via unvalidated endpointslice and serviceimport ips

Assigner: redhat
Reserved: 27.07.2026 Published: 20.08.2026 Updated: 20.08.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N
CVSS Score: 8.7

Product Status

Vendor Red Hat
Product Red Hat Advanced Cluster Management for Kubernetes 2
Versions Default: affected
Vendor Red Hat
Product Red Hat Advanced Cluster Management for Kubernetes 2
Versions Default: affected
Vendor Red Hat
Product Red Hat Advanced Cluster Management for Kubernetes 2
Versions Default: affected
Vendor Red Hat
Product Red Hat Advanced Cluster Management for Kubernetes 2
Versions Default: affected

Workarounds

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.

References

Problem Types

  • Insufficient Verification of Data Authenticity CWE