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CloudstackApplication · Apache

CVE-2025-26521

HIGH · 8.1 CVSS v3.1 Published 2025-06-10
Fix available
A fix is available. Upgrade to 4.19.3.0 / 4.20.1.0 or later.
See remediation →
87/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
When an Apache CloudStack user-account creates a CKS-based Kubernetes cluster in a project, the API key and the secret key of the 'kubeadmin' user of the caller account are used to create the secret config in the CKS-based Kubernetes cluster. A member of the project who can access the CKS-based Kubernetes cluster, can also access the API key and secret key of the 'kubeadmin' user of the CKS cluster's creator's account. An attacker who's a member of the project can exploit this to impersonate and perform privileged actions that can result in complete compromise of the confidentiality, integrity, and availability of resources owned by the creator's account. CKS users are recommended to upgrade to version 4.19.3.0 or 4.20.1.0, which fixes this issue.Updating Existing Kubernetes Clusters in ProjectsA service account should be created for each project to provide limited access specifically for Kubernetes cluster providers and autoscaling. Follow the steps below to create a new service account, update the secret inside the cluster, and regenerate existing API and service keys:1. Create a New Service AccountCreate a new account using the role "Project Kubernetes Service Role" with the following details: Account Name kubeadmin-<FIRST_EIGHT_CHARACTERS_OF_PROJECT_ID> First Name Kubernetes Last Name Service User Account Type 0 (Normal User) Role ID <ID_OF_SERVICE_ROLE> 2. Add the Service Account to the ProjectAdd this account to the project where the Kubernetes cluster(s) are hosted. 3. Generate API and Secret KeysGenerate API Key and Secret Key for the default user of this account. 4. Update the CloudStack Secret in the Kubernetes ClusterCreate a temporary file `/tmp/cloud-config` with the following data:    api-url = <API_URL>     # For example: <MS_URL>/client/api   api-key = <SERVICE_USER_API_KEY>   secret-key = <SERVICE_USER_SECRET_KEY>   project-id = <PROJECT_ID> Delete the existing secret using kubectl and Kubernetes cluster config:    ./kubectl --kubeconfig kube.conf -n kube-system delete secret cloudstack-secret Create a new secret using kubectl and Kubernetes cluster config:     ./kubectl --kubeconfig kube.conf -n kube-system create secret generic cloudstack-secret --from-file=/tmp/cloud-config Remove the temporary file:     rm /tmp/cloud-config5. Regenerate API and Secret KeysRegenerate the API and secret keys for the original user account that was used to create the Kubernetes cluster.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In Apache CloudStack, when a user creates a CKS-based Kubernetes cluster within a project, the API key and secret key of the 'kubeadmin' user are embedded in the cluster's secret configuration. Any project member with cluster access can retrieve these credentials, enabling impersonation of the cluster creator and privileged actions across their account resources.

MitigationUpgrade to CloudStack 4.19.3.0 or 4.20.1.0. For existing clusters, manually migrate to a per-project service account with limited 'Project Kubernetes Service Role' and regenerate all exposed API/secret keys.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
CloudstackApplication
Affected:>= 4.17.0.0, < 4.19.3.0>= 4.20.0.0, < 4.20.1.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify CloudStack version is affected
    Determine the installed Apache CloudStack management server version and compare against the affected ranges: >= 4.17.0.0 to < 4.19.3.0, or >= 4.20.0.0 to < 4.20.1.0
    Affected if Installed version falls within one of these ranges
  2. Identify CKS Kubernetes clusters
    Query CloudStack for any Kubernetes clusters created using the CloudStack Kubernetes Service (CKS) feature
    Affected if Any CKS-based clusters exist in the environment
  3. Check cluster project association
    Determine whether CKS clusters were created within a project scope rather than at domain or root level
    Affected if Clusters were created within a project context and are accessible to project members
  4. Inspect cluster secret configuration
    Review the cluster's configuration or metadata for embedded API key and secret key values associated with the kubeadmin user
    Affected if kubeadmin API credentials are present and retrievable by project members with cluster access

Environment is affected if running an affected CloudStack version with CKS clusters created within projects, where cluster configuration exposes kubeadmin credentials to all project members.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.19.3.0 / 4.20.1.0 or later
Fixed in 4.19.3.04.20.1.0
Interim mitigation

Upgrade to CloudStack 4.19.3.0 or 4.20.1.0. For existing clusters, manually migrate to a per-project service account with limited 'Project Kubernetes Service Role' and regenerate all exposed API/secret keys.

Recommended fix High confidence

4.19.3.0 or 4.20.1.0

  1. Upgrade Apache CloudStack to version 4.19.3.0 or 4.20.1.0 to resolve the vulnerability
  2. For existing CKS clusters in projects, create a new service account with role 'Project Kubernetes Service Role' using account name format 'kubeadmin-<FIRST_EIGHT_CHARACTERS_OF_PROJECT_ID>'
  3. Add the newly created service account to the project where the Kubernetes cluster(s) are hosted
  4. Generate API Key and Secret Key for the default user of this new service account
  5. Delete the existing cloudstack-secret from the Kubernetes cluster using: ./kubectl --kubeconfig kube.conf -n kube-system delete secret cloudstack-secret
  6. Create a new secret using the service account credentials: ./kubectl --kubeconfig kube.conf -n kube-system create secret generic cloudstack-secret --from-file=/tmp/cloud-config
  7. Regenerate API and Secret Keys for the original user account that was used to create the Kubernetes cluster

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Cloudstack Scoped from the published advisory
  • Consultation6.0 h
  • Implementation10.0 h
  • Testing6.0 h
  • Review / QA4.0 h
26.0 hours of engineering $4,620
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

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Peer-ranked notes from engineers who’ve handled CVE-2025-26521 in production — separate from our analysis above.

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