A flaw was found in Rancher Manager. Project Secrets were propagated into a namespace based only on its field.cattle.io/projectId annotation, without verifying that the referenced project belonged to the same downstream cluster. A user able to create namespaces on one cluster could set the annotation to a project ID from another cluster and have that project's secrets copied into a namespace under their control.

This issue affects Rancher: before 2.15.1.

A flaw was found in Rancher Manager. The GlobalRole controller derived the target ClusterRole name from the user-settable authz.management.cattle.io/cr-name annotation and overwrote that object's rules without verifying ownership. A user with delegated GlobalRole create or update permission could point the annotation at any existing ClusterRole, such as cluster-admin, and revoke the permissions of every principal bound to it. The change persists after the malicious GlobalRole is deleted.

This issue affects Rancher: before 2.15.1.

A privilege escalation vulnerability exists in Rancher's impersonation middleware (pkg/auth/requests/impersonate.go). An authenticated Rancher user with the default user global role can gain full administrative access to the Rancher control plane and transitively to all downstream clusters it manages.

This issue affects Rancher: from 2.11.0 before 2.11.16, from 2.12.0 before 2.12.12, from 2.13.0 before 2.13.8, and from 2.14.0 before 2.14.2.

A path traversal vulnerability was found in Fleet's ImageScan subsystem in Rancher Fleet 0.12.0 up to 0.12.16, 0.13.0 up to 0.13.12, 0.14.0 up to 0.14.7 and 0.15.0 up to 0.15.3 could be used to traverse outside of the intended directory, causing a denial of service.

A Rancher FleetWorkspace admission path allowed side effects to occur in the Rancher webhook handler for versions 0.7.0 up to 0.7.10, 0.8.0 up to 0.8.7, 0.9.0 up to 0.9.6 and 0.10.0 up to 0.10.7. An unauthenticated attacker with network access to the in-cluster rancher-webhook service could submit a crafted admission payload and cause workspace-related Kubernetes objects to be created with attacker-chosen identity data.

A missing clean-up in the legacy Project Role Template Binding (PRTB) reconciler in Rancher versions 2.13.0 up to 2.13.7 and 2.14.0 up to 2.14.3 allowed users to retain unauthorized Pod Security Admission (PSA) permissions after an administrator removes those permissions from a RoleTemplate.

Impact A vulnerability has been identified within Rancher Manager in the GitHub App authentication provider. When evaluating permissions, the provider incorrectly expands user team memberships to include all teams within the associated GitHub organization, rather than restricting access to the specific teams to which the user actually belongs.

Specifically, when a user authenticates via the GitHub App provider, Rancher's team membership evaluation logic incorrectly handles cached data. Instead of checking the user-specific list, the evaluation logic iterates over all teams defined within the entire GitHub organization. The authentication provider should consult the correctly cached, per-user membership list to assign the user's specific group permissions. Consequently, any authenticated user who belongs to at least one team in a GitHub organization is mistakenly granted group principals for every team within that entire organization during authentication and authorization checks.

This issue allows a malicious user who is a member of a low-privilege team within a GitHub organization to gain unauthorized access to or permissions for any other team in that organization. If those other teams are bound to Rancher login allowlists or RBAC roles (cluster-level, project-level, or global), the attacker can pass access checks that should otherwise fail, inheriting permissions they were never granted.

Exploitation of this vulnerability requires the following conditions to be met: - The GitHub App authentication provider must be enabled and configured for the target GitHub organization. - The attacker must possess a valid GitHub account with membership in at least one team within that target organization. - A separate team within the same GitHub organization must be explicitly mapped to Rancher RBAC roles or specified within Rancher's login allowlist (allowedPrincipalIds).

Please consult the associated MITRE ATT&CK - Technique - Valid Accounts for further information about this category of attack.

Patches This fix corrects the team listing logic to iterate only the teams stored in the per-user membership cache and includes a one-time startup migration that marks all affected User resources for refresh, forcing Rancher to rebuild group principals using the now-corrected logic.

Patched versions of Rancher include releases v2.14.2 and v2.13.6.

Workarounds If upgrading to a patched version immediately is not feasible, users are encouraged to consider these temporary mitigations: - Disable GitHub App authentication provider and switch to an alternative authentication provider (GitHub OAuth). - Remove or restrict team-based group principals from allowed principalIds. - Audit and temporarily remove RBAC bindings (GlobalRoleBindings, ClusterRoleTemplateBindings, ProjectRoleTemplateBindings) that reference GitHub App team principals until the patch is applied. - Disable provider refresh and clean up inflated group membership for users (manually or by writing a script).

These workarounds reduce the attack surface but do not eliminate the vulnerability. Existing user sessions and cached principals remain inflated until a provider refresh occurs. Upgrading to a patched version is strongly recommended.

References If you have any questions or comments about this advisory: - Reach out to the SUSE Rancher Security team for security related inquiries. - Open an issue in the Rancher repository. - Verify with our support matrix and product support lifecycle.

Impact A critical command injection vulnerability has been identified in the Rancher Manager cluster import endpoint /v3/import/{token}{clusterId}.yaml through unsanitized YAML parameters. This endpoint accepts an authImage query parameter that is rendered without sanitization into a generated Kubernetes manifest template. By including URL-encoded newlines in the parameter value, an attacker can break out of the image: field to inject arbitrary YAML keys and malicious configurations, such as commands to execute malicious containers.

Exploitation of this vulnerability requires the following conditions to be met: - Attackers must obtain a valid cluster registration token (these tokens may be exposed, for example, through documentation, screenshots, or insecure communication channels). - The victim’s cluster operator must execute kubectl apply against a maliciously crafted URL.

When a victim applies this compromised manifest using kubectl apply, a DaemonSet is deployed with the injected configuration. This DaemonSet: - Runs on all control-plane nodes with hostNetwork: true enabled. - Uses the cattle service account, which possesses cluster-admin privileges. - Mounts /etc/kubernetes directly from the host. - Executes attacker-controlled commands via the injected command: field.

An attacker who successfully exploits this vulnerability could:

- Achieve full control over downstream Kubernetes clusters. - Execute arbitrary code on control-plane nodes with elevated privileges. - Access sensitive cluster secrets and configurations via the privileged service account. - Disrupt cluster operations by manipulating critical control-plane workloads. - Establish persistent access through the deployed DaemonSet.

Note: If you believe that you might have been impacted by this vulnerability, it's highly advised to review your clusters' logs and deployment logs for signs of malicious deployments and to rotate all service accounts and credentials that might have been exposed in such a scenario.

Please refer to the associated MITRE ATT&CK - Technique - Deploy Container for further information about this category of attack.

Patches This vulnerability is addressed by validating the authImage parameter to ensure it contains only valid OCI image reference characters, rejecting any input containing newlines, whitespace, or other characters that could break YAML syntax.

Patched versions of Rancher include release v2.14.2, v2.13.6, v2.12.10, v2.11.14 and v2.10.12.

Workarounds If upgrading to a patched version immediately is not feasible, users are encouraged to apply the following workaround:

- Review the kube-api-auth DaemonSet: Inspect downstream clusters for the kube-api-auth DaemonSet within the cattle-system namespace (which targets control-plane nodes). Review this resource configuration carefully for: - Unexpected command: or args: fields in the container specification. - References to non-standard or suspicious container images. - Any modifications occurring after the initial cluster import. - Validate manifest integrity: Before running kubectl apply on any import manifests, verify that the source URLs originate from trusted sources and match expected patterns.

Credits

This security issue was reported by the following collaborators according to our responsible disclosure policy:

- Radisauskas Arnoldas from NATO and the NATO Cyber Security Centre (NCSC). - Michael Wollner from Deutsche Telekom AG.

References If you have any questions or comments about this advisory: - Reach out to the SUSE Rancher Security team for security related inquiries. - Open an issue in the Rancher repository. - Verify with our support matrix and product support lifecycle.

Impact

A flaw discovered in Rancher versions from 2.5.0 up to and including 2.5.9 allows an authenticated user to impersonate any user on a cluster through the Steve API proxy, without requiring knowledge of the impersonated user's credentials. This is due to the Steve API proxy not dropping the impersonation header before sending the request to the Kubernetes API. A malicious user with authenticated access to Rancher could use this to impersonate another user with administrator access in Rancher, receiving, then, administrator level access in the cluster.

Patches Patched versions include releases 2.5.10, 2.6.0 and later versions.

Workarounds Limit access in Rancher to trusted users. There is not a direct mitigation besides upgrading to the patched Rancher versions.

For more information If you have any questions or comments about this advisory: Reach out to SUSE Rancher Security team for security related inquiries. Open an issue in Rancher repository. Verify our support matrix and product support lifecycle.

Impact This vulnerability only affects customers using group based authentication in Rancher versions up to and including 2.4.17, 2.5.11 and 2.6.2.

When removing a Project Role associated to a group from a project, the bindings that grant access to cluster scoped resources for those subjects do not get deleted. This happens due to an incomplete authorization logic check. A user who is a member of an affected group with authenticated access to Rancher could use this to access resources they should no longer have access to. The exposure level will depend on the original permission level granted to the affected project role.

Patches Patched versions include releases 2.4.18, 2.5.12, 2.6.3 and later versions.

Workarounds Limit access in Rancher to trusted users. There is not a direct mitigation besides upgrading to the patched Rancher versions.

References Cluster and project roles documentation for Rancher 2.6, 2.5 and 2.4.

For more information If you have any questions or comments about this advisory: Reach out to SUSE Rancher Security team for security related inquiries. Open an issue in Rancher repository. Verify our support matrix and product support lifecycle.

A Reliance on Untrusted Inputs in a Security Decision vulnerability in Rancher allows users in the cluster to act as others users in the cluster by forging the "Impersonate-User" or "Impersonate-Group" headers. This issue affects: Rancher versions prior to 2.5.9. Rancher versions prior to 2.4.16.

A Improper Access Control vulnerability in Rancher, allows users in the cluster to make request to cloud providers by creating requests with the cloud-credential ID. Rancher in this case would attach the requested credentials without further checks This issue affects: Rancher versions prior to 2.5.9; Rancher versions prior to 2.4.16.

A Incorrect Permission Assignment for Critical Resource vulnerability in Rancher allows users in the cluster to modify resources they should not have access to. This issue affects: Rancher versions prior to 2.5.9 ; Rancher versions prior to 2.4.16.