CVE-2026-66878Network attack vector

Cross-namespace Secret disclosure via user-controlled reference

Published Aug 12, 2026 · Updated Aug 12, 2026

Authorization bypass in Red Hat Advanced Cluster Management for Kubernetes 2 allows remote authenticated users to read Secrets from other namespaces. The multicloud-operators-subscription FetchChannelReferences path honors tenant-controlled Channel.spec.secretRef.namespace and copies the referenced Secret into the tenant namespace. Exploitation requires namespace-administrator rights to create Channel and Subscription resources; disclosed impact is limited to Secret confidentiality.

CVSS severity7.7
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Red Hat Advanced Cluster Management for Kubernetes 2 allows remote authenticated users to read Secrets from other namespaces. The multicloud-operators-subscription FetchChannelReferences path honors tenant-controlled Channel.spec.secretRef.namespace and copies the referenced Secret into the tenant namespace. Exploitation requires namespace-administrator rights to create Channel and Subscription resources; disclosed impact is limited to Secret confidentiality.

The record

CVE
CVE-2026-66878
Published
Aug 12, 2026
Updated
Aug 12, 2026
Vendor
389 Directory Server
Product
Red Hat Advanced Cluster Management for Kubernetes
Classifications
CWE-639, T1552.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

389 Directory Server · Red Hat Advanced Cluster Management for KubernetesAffected versions are unavailable in this record.

Published CVSS scores

7.7Red HatCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1552.007Unsecured Credentials: Container API

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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