CVE-2026-66787
Lighthouse: lighthouse: cross-cluster dns spoofing via unvalidated endpointslice ip addresses
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.
INFO
Published Date :
Aug. 20, 2026, 7:16 p.m.
Last Modified :
Oct. 19, 2026, 5:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-66787
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 53f830b8-0a3f-465b-8143-3b8a9948e749 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update lighthouse component to validate IP addresses.
- Ensure EndpointSlice objects are properly sanitized.
- Monitor for suspicious EndpointSlice configurations.
- Review network traffic for anomalies.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-66787.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-66787 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-66787
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-66787 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-66787 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Oct. 19, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/66xxx/CVE-2026-66787.json">CVE-2026-66787</a> Added Reference https://access.redhat.com/errata/RHSA-2026:85227 -
CVE Translated by [email protected]
Oct. 18, 2026
Action Type Old Value New Value Added Translation Title: Red Hat Advanced Cluster Management for Kubernetes 2 de Red Hat, Description: Se encontró una falla en el componente lighthouse de Red Hat Advanced Cluster Management para Kubernetes. Esta vulnerabilidad se origina en la validación insuficiente de las direcciones IP anunciadas dentro de los objetos EndpointSlice. Un clúster spoke comprometido puede explotar esto creando EndpointSlices con direcciones IP controladas por el atacante, haciendo que el DNS lighthouse de otros clústeres redirija el tráfico de servicio legítimo a puntos finales maliciosos. Esto permite a un atacante remoto realizar ataques transparentes de Man-in-the-Middle (MitM) en comunicaciones de servicio entre clústeres, lo que podría llevar a la revelación de información no autorizada y manipulación de datos. -
CVE Modified by [email protected]
Oct. 12, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N Removed CVSS V3.1 AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L Added CWE CWE-345 Removed CWE CWE-489 -
CVE Modified by [email protected]
Sep. 03, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/66xxx/CVE-2026-66787.json">CVE-2026-66787</a> Added Reference https://access.redhat.com/errata/RHSA-2026:63016 -
CVE Modified by [email protected]
Sep. 01, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L -
CVE Modified by [email protected]
Sep. 01, 2026
Action Type Old Value New Value Removed CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N Added CWE CWE-489 Removed CWE CWE-345 Added Reference https://access.redhat.com/security/cve/CVE-2026-66787 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2507532 Removed Reference https://access.redhat.com/security/cve/CVE-2026-66787 Removed Reference https://bugzilla.redhat.com/show_bug.cgi?id=2507532 -
New CVE Received by [email protected]
Aug. 20, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'packageName': 'rhacm2/lighthouse-agent-rhel9', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'packageName': 'rhacm2/lighthouse-coredns-rhel9', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'packageName': 'rhacm2/subctl-rhel9', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'packageName': 'rhacm2/submariner-rhel9-operator', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}] 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. Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N Added CWE CWE-345 Added Reference https://access.redhat.com/security/cve/CVE-2026-66787 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2507532 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 20, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-66787', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-20T18:51:33.566517Z'}