CVE-2026-42183: Argoproj Argo Workflows

Medium severity, CVSS 6.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. From version 4.0.0 to before version 4.0.5, a nil pointer dereference in server/auth/gatekeeper.go rbacAuthorization() causes a panic (denial of service) for SSO users whose claims match a namespace-level RBAC rule but not an SSO-namespace rule, when SSO_DELEGATE_RBAC_TO_NAMESPACE=true. This issue has been patched in version 4.0.5.

Affected products

• Argoproj Argo Workflows: from 4.0.0, before 4.0.5 (fixed in 4.0.5)

Published 2026-05-09. Last modified 2026-07-24.