CVE-2026-66794
Cluster-proxy-addon: cluster-proxy-addon: unauthenticated ssrf to arbitrary managed-cluster services via public route
No known exploitation. EPSS puts it in the 47th percentile. Only a workaround so far.
What to do
No fixed build is published yet. The vendor describes a workaround.
What it is
From the CVE record
A flaw was found in the `cluster-proxy-addon` component of Multicluster Engine for Kubernetes. This vulnerability allows an unauthenticated attacker, who can access the user-facing route, to bypass authentication and authorization checks. By manipulating URL path segments, the attacker can proxy requests to arbitrary services across any managed cluster. This enables unauthorized access to internal services that would otherwise be protected, potentially leading to information disclosure or further compromise of the cluster environment.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.6% chance of exploitation activity in the next 30 days, which ranks it in the 47th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
19 events over 20 days, from the signal feeds we watch.
- Workaround availablerecord updated
- Workaround availablerecord updated
- Workaround availablerecord updated
- Workaround availableworkaround available, record updated, record updated
- Workaround availablerecord updated
- Workaround availablerecord updated
Affected products
- multicluster engine for Kubernetes 2.1Operating Systems / linux-distro
- multicluster engine for Kubernetes 2.11Cloud & SaaS / container-orchestration
- multicluster engine for Kubernetes 2.17Operating Systems / linux-distro
- multicluster engine for Kubernetes 2.6Cloud & SaaS / container-orchestration
- multicluster engine for Kubernetes 2.8Cloud & SaaS / container-orchestration
- multicluster engine for Kubernetes 2.9Cloud & SaaS / container-orchestration
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Scored 9.3 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Command and ControlT1090Proxyhigh confidence
- Initial AccessT1190Exploit Public-Facing Applicationmedium confidence
Sources
References in the record
- access.redhat.com/errata/RHSA-2026:59556
- access.redhat.com/errata/RHSA-2026:59557
- access.redhat.com/errata/RHSA-2026:59558
And 5 more references. See all after sign-in
In the news
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