CVE-2026-45726

Omni supports importing standalone Talos clusters.

During this process, an ImportedClusterSecrets resource is created, which contains the full CA secrets bundle for the cluster being imported.

If these secrets are not rotated by the importing actor, an authenticated Omni user with Reader access can read this resource and gain full access to the Talos, Kubernetes and etcd APIs of the cluster.

Severity

• Attack Vector: Adjacent: the attacker needs to be in the same network to be able to access Talos/Kubernetes APIs with the compromised keys.
• Attack Complexity: High: the attacker needs a deep understanding of Omni's internals. The resource is only created for imported clusters, and is normally not represented to users via any high-level API.
• Privileges Required: Low: the role Reader is sufficient for the attacker to be able to read an imported cluster's secrets.
• User Interaction: Required: another user must have imported a cluster to Omni for this vulnerability to exist.
• Scope: Changed: the leaked CA private keys let an attacker directly get full control on Kubernetes or Talos, beyond the limitations enforced by Omni.
• Confidentiality Impact: High: full cluster CA private keys (Kubernetes, Talos, etcd, service account) are exposed.
• Integrity Impact: High: with the CA keys the attacker has full control on Kubernetes and Talos of the compromised (imported) cluster, and modify the workloads on it.
• Availability Impact: High: with the CA keys the attacker has full control on Kubernetes and Talos of the compromised (imported) cluster, and modify the workloads on it.

Credit

This vulnerability was discovered and reported by bugbunny.ai.

• Any Reader-level account can exfiltrate the complete CA private key hierarchy (Kubernetes CA, etcd CA, service account key) of the imported clusters whose secrets are not yet rotated ("tainted" imported clusters).
• With the Kubernetes CA private key, an attacker can sign certificates for any Kubernetes user or group, including system:masters, achieving cluster-admin access to the imported cluster entirely outside Omni's control plane.
• Impact scope extends beyond Omni to every Kubernetes workload, credential, and secret stored in the affected imported cluster.

A file, directory, or other resource is assigned permissions that allow broader access than intended. Typical impact: unauthorized read, modification, or execution of the resource.

CVE-2026-45726 has a CVSS score of 7.6 (High). The vector is reachable from an adjacent network, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.6.6, 1.7.3); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-45726? CVE-2026-45726 is a high-severity incorrect permission assignment for critical resource vulnerability in github.com/siderolabs/omni (go), affecting versions >= 1.3.0, < 1.6.6. It is fixed in 1.6.6, 1.7.3. A file, directory, or other resource is assigned permissions that allow broader access than intended.
2. How severe is CVE-2026-45726? CVE-2026-45726 has a CVSS score of 7.6 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/siderolabs/omni are affected by CVE-2026-45726? github.com/siderolabs/omni (go) versions >= 1.3.0, < 1.6.6 is affected.
4. Is there a fix for CVE-2026-45726? Yes. CVE-2026-45726 is fixed in 1.6.6, 1.7.3. Upgrade to this version or later.
5. Is CVE-2026-45726 exploitable, and should I be worried? Whether CVE-2026-45726 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-45726 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-45726?
   • Upgrade github.com/siderolabs/omni to 1.6.6 or later
   • Upgrade github.com/siderolabs/omni to 1.7.3 or later