Vulnerability in Red Hat Advanced Cluster Management For Kubernetes 2

CVE-2026-66787

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.

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-66787?
CVE-2026-66787 is a high-severity vulnerability in Red Hat Advanced Cluster Management For Kubernetes 2, classified under Insufficient Verification of Data Authenticity. CVSS score: 8.7/10. Published 2026-08-20.
How severe is CVE-2026-66787?
High severity. CVSS v3 base score is 8.7 out of 10.