Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-66878

CVE-2026-66878HIGH

Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.11 — Multicloud-operators-subscription: multicloud-operators-subscription: fetchchannelreferences honours channel.spec.secretref.namespace enabling cross-namespace secret exfiltration

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   L   N  C  H  N  N    7.7   .0048   39.5     —

AFFECTED
  Product                                                  Versions     Fixed
  Red Hat Advanced Cluster Management for Kubernetes 2.11  unspecified  1787263584
  Red Hat Advanced Cluster Management for Kubernetes 2.13  unspecified  1787263693
  Red Hat Advanced Cluster Management for Kubernetes 2.14  unspecified  1787170830
  Red Hat Advanced Cluster Management for Kubernetes 2.15  unspecified  1787240030
  Red Hat Advanced Cluster Management for Kubernetes 2.16  unspecified  1787242321
  Red Hat Advanced Cluster Management for Kubernetes 2.17  unspecified  1787242108

TIMELINE
  Aug 11  Reserved by redhat
  Aug 12  Published (CNA: redhat)
  Aug 26  PATCH SHIPPED — CVE-2026-66878 (Red Hat Advanced Cluster Management for Kubernetes 2.11). Fixed in Red Hat Advanced Cluster Management for Kubernetes 2.11 1787263584.

CWE-639 · CNA: redhat · CVSS v3.1 · 8 references · NVD status: Awaiting Analysis

Description

A flaw was found in multicloud-operators-subscription. A privileged user, specifically a namespace administrator capable of creating Channel and Subscription resources, can exploit this vulnerability. By manipulating the Channel.Spec.SecretRef.Namespace field, the user can cause the system to copy sensitive Secret contents from other namespaces into their own, leading to information disclosure.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
August 11, 2026	Reserved	Reserved by redhat
August 12, 2026	Published	Published (CNA: redhat)
August 26, 2026	PATCH SHIPPED	PATCH SHIPPED — CVE-2026-66878 (Red Hat Advanced Cluster Management for Kubernetes 2.11). Fixed in Red Hat Advanced Cluster Management for Kubernetes 2.11 1787263584.

Affected

Affected products and packages — 6 rows
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.11	—	—	1787263584
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.13	—	—	1787263693
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.14	—	—	1787170830
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.15	—	—	1787240030
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.16	—	—	1787242321
Red Hat	Red Hat Advanced Cluster Management for Kubernetes 2.17	—	—	1787242108

Weaknesses

CWE-639

References (8)

https://access.redhat.com/errata/RHSA-2026:60386 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:60387 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:60388 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:60389 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:60390 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:60391 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/security/cve/CVE-2026-66878 [vdb-entry, x_refsource_REDHAT]
https://bugzilla.redhat.com/show_bug.cgi?id=2514226 [issue-tracking, x_refsource_REDHAT]

Authoritative record: CVE-2026-66878 at cve.org

Vendors: red hat

Weaknesses: CWE-639

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-66878 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.