# CVE-2026-71576: Red Hat Multicluster Global Hub authentication bypass in Kafka CloudEvents

Source: https://junglewise.ai/threats/cve-2026-71576-red-hat-multicluster-global-hub-authentication-bypass-in-kafka  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-10. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-71576 · Severity: high · CVSS 8.5 · Published 2026-08-10

Red Hat Multicluster Global Hub is a management platform that aggregates and controls multiple Kubernetes clusters across organizations. The manager component fails to properly verify the identity of incoming messages on Kafka, allowing an attacker who has compromised one cluster and obtained its certificate to forge messages and corrupt critical data (compliance status, inventory, cluster health) across other managed clusters in the system.

Technologies: [Red Hat Multicluster Global Hub](https://junglewise.ai/threats/technologies/multicluster-global-hub). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-71576 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-71576 being exploited in the wild.

**How severe is CVE-2026-71576?** High severity, with a CVSS score of 8.5, published 10 August 2026.

**Which products and versions are affected?** Red Hat Multicluster Global Hub before 1.4.9.

**Is there a fix for CVE-2026-71576?** A patch was published on 2026-09-15: Fixed in Multicluster Global Hub 1.4.9 (RHSA-2026:67516) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-71576 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-71576?** Check whether you run Red Hat Multicluster Global Hub at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an authentication bypass in the manager component's validation of CloudEvents received from Kafka status topics. The root cause is improper verification of source identity claims in incoming messages, which are self-asserted rather than cryptographically verified. An attacker who has compromised a managed hub and obtained its Kafka client certificate can manipulate the source identity field to impersonate other hubs, sending malicious CloudEvents to the manager. This allows arbitrary modification or deletion of compliance, inventory, and cluster health data in the database. The attack requires prior compromise of a managed hub to obtain valid Kafka credentials, limiting the immediate attack surface. Patches are available in Multicluster Global Hub 1.4.9 and later.

## Affected products

- Red Hat Multicluster Global Hub before 1.4.9

## Timeline

- 2026-08-10: disclosed
- 2026-09-15: patched: Fixed in Multicluster Global Hub 1.4.9 (RHSA-2026:67516)

## References

- [https://catalog.redhat.com/software/containers/](https://catalog.redhat.com/software/containers/)
- [https://access.redhat.com/errata/RHSA-2026:67516](https://access.redhat.com/errata/RHSA-2026:67516)

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