CVE-2026-94290: SUSE Rancher Fleet privilege escalation in agent controller

CVE-2026-94290 · Severity: critical · CVSS 9.1 · Published 2026-11-02

SUSE Rancher Fleet is a tool for managing and deploying applications across multiple Kubernetes clusters. An authenticated user with minimal permissions could exploit a weakness in how Fleet validates kubeconfig credentials, gaining full administrative control over the Rancher management cluster and, by extension, all clusters managed by that Rancher installation. This enables attackers to steal credentials for downstream clusters, disable services, and deploy malicious workloads.

Technologies: Suse Rancher Fleet. Vendors: Suse.

Quick answers

Is CVE-2026-94290 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-94290 being exploited in the wild.
How severe is CVE-2026-94290?
Critical severity, with a CVSS score of 9.1, published 2 November 2026.
Which products and versions are affected?
Suse Rancher Fleet 0.16.0 to 0.16.3, 0.15.0 to 0.15.8, 0.14.0 to 0.14.12, 0.13.0 to 0.13.17, and possibly earlier versions.
Is there a fix for CVE-2026-94290?
Yes: fixed in Rancher Fleet 0.16.3, 0.15.8, 0.14.12, 0.13.17. Until then: Restrict Fleet workspace self-service by removing the create verb on management.cattle.io fleetworkspaces from standard user roles. Additionally, restrict write access to fleet.cattle.io clusters and bundles in non-system namespaces to administrators and trusted operators only. As a temporary compatibility measure, the Helm value allowUnlabeledKubeConfigSecretNamespaces can be set to true to accept unlabeled secrets in well-known Fleet namespaces, but this should only be used until affected secrets are properly labeled and should be disabled afterward. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-94290 attacked?
It is attacked over the network.
Am I affected by CVE-2026-94290?
Check whether you run Suse Rancher Fleet 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.

How to fix

  • Fixed in: Rancher Fleet 0.16.3, 0.15.8, 0.14.12, 0.13.17

Restrict Fleet workspace self-service by removing the create verb on management.cattle.io fleetworkspaces from standard user roles. Additionally, restrict write access to fleet.cattle.io clusters and bundles in non-system namespaces to administrators and trusted operators only. As a temporary compatibility measure, the Helm value allowUnlabeledKubeConfigSecretNamespaces can be set to true to accept unlabeled secrets in well-known Fleet namespaces, but this should only be used until affected secrets are properly labeled and should be disabled afterward.

Technical details

The Fleet agent management controller runs with cluster-admin privileges on the Rancher local cluster but failed to properly validate which kubeconfig secrets a Fleet Cluster object could reference. An attacker could create a Fleet Cluster object in a namespace they control that references a kubeconfig secret containing management cluster credentials from a different namespace, causing the controller to execute the attacker's Fleet content with cluster-admin privileges. The fix introduces a label-based authorization mechanism (fleet.cattle.io/kubeconfig-referenceable-from) to restrict secret references across namespaces.

Affected products

  • SUSE Rancher Fleet 0.16.0 to 0.16.3, 0.15.0 to 0.15.8, 0.14.0 to 0.14.12, 0.13.0 to 0.13.17, and possibly earlier versions

Timeline

  • 2026-10-29: disclosed: GitHub Security Advisory GHSA-qfmw-gw96-ffcr published
  • 2026-11-02: advisory: CVE-2026-94290 published on NVD

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.