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 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:63016
https://access.redhat.com/security/cve/CVE-2026-66787
https://bugzilla.redhat.com/show_bug.cgi?id=2507532

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-20 19:16

Updated : 2026-09-03 13:06

NVD link : CVE-2026-66787

Mitre link : CVE-2026-66787

CVE.ORG link : CVE-2026-66787

JSON object : View

Products Affected

No product.

CWE

CWE-489

Active Debug Code

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