Argo CD: ServerSideDiff exposes cleartext Kubernetes Secret data to users with app read access

Impact

When ServerSideDiff is enabled, the diff Argo CD computes and shows for an Application includes the cleartext contents of Kubernetes Secrets instead of redacting them. On a GPU cluster this is how registry pull credentials, model-store and object-store keys, license tokens for the GPU stack and in-cluster service account tokens leak to anyone who can read an Application in the Argo CD UI or API - a far wider group than those who hold get secrets RBAC in the target namespace. Because GitOps controllers typically manage every tenant namespace from one place, a single low-privileged Argo CD reader can reach secrets for workloads they do not otherwise touch. Scope is changed (S:C in the vector): the flaw is in Argo CD, the data belongs to the clusters it manages.

Who can reach it

Authenticated Argo CD user with read access to an Application (low privilege, network reachable); no cluster-level secret permissions needed. Only deployments on 3.2.0-3.2.10 or 3.3.0-3.3.8 with ServerSideDiff in use are affected.

What to do

Upgrade Argo CD to 3.2.11 or 3.3.9 (Red Hat OpenShift GitOps users take the corresponding RHSA). This is a control-plane component upgrade - restart of the argocd-server/repo-server/application-controller pods, no node drain and no tenant workload impact. If the upgrade cannot be scheduled immediately, disabling ServerSideDiff removes the exposure, and any secret already rendered in a diff should be treated as disclosed and rotated.

References

Related entries

• RHACM multicloud-operators-channel: managed-cluster agent reads all Secrets in hub Channel namespacesCVE-2026-73122 · Red Hat Advanced Cluster Management multicloud-operators-channel (hub subscription controller)High
• RHACM subscription controller: HelmRelease secretRef.Namespace reads Secrets from any namespaceCVE-2026-73137 · Red Hat Advanced Cluster Management multicloud-operators-subscription (HelmRelease secretRef)High
• OpenShift console: authenticated user makes the console pod fetch arbitrary URLs via a Helm chart URL (SSRF)CVE-2026-75888 · Red Hat OpenShift Container Platform console (Helm chart URL fetch)High
• RHACS Central: unbounded GraphQL query depth lets an authenticated user stall the management planeCVE-2026-9165 · Red Hat Advanced Cluster Security for Kubernetes (Central GraphQL API, query depth limit)High
• KubeVirt: Symlink path traversal in the virt-exportserver VMExport directory endpointCVE-2026-9804 · KubeVirtHigh
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