CVE-2026-66787

medium

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.

References

https://github.com/sm-ard/devops-pulse

https://bugzilla.redhat.com/show_bug.cgi?id=2507532

https://access.redhat.com/security/cve/CVE-2026-66787

https://access.redhat.com/errata/RHSA-2026:63016

Details

Source: Mitre, NVD

Published: 2026-08-20

Updated: 2026-09-03

Risk Information

CVSS v2

Base Score: 7.7

Vector: CVSS2#AV:N/AC:L/Au:M/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 5.4

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

Severity: Medium

EPSS

EPSS: 0.00172