CVE-2026-42880: argoproj/argo-cd: Argo CD: Information disclosure of Kubernetes Secret data via Server-Side Apply dry-run mechanism

Severity: Critical

CVSS Score: 9.6

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. From versions 3.2.0 to before 3.2.11 and 3.3.0 to before 3.3.9, there is a missing authorization and data-masking gap in Argo CD's ServerSideDiff endpoint that allows an attacker with read-only access to extract plaintext Kubernetes Secret data from etcd via the Kubernetes API server's Server-Side Apply dry-run mechanism. This issue has been patched in versions 3.2.11 and 3.3.9.