Argo Workflows versions before 3.7.14 and 4.0.5 contain an incorrect authorization vulnerability (CWE-863) where users with create Workflow permission can bypass the templateReferencing: Strict enforcement. This bypass allows escalation of privileges such as gaining host network access, switching service accounts, overriding pod security contexts, adding tolerations to schedule on control-plane nodes, and enabling service account token mounting. The vulnerability undermines the intended security controls of the Strict mode feature. The practical impact varies depending on additional Kubernetes admission controls like PodSecurity admission or OPA/Gatekeeper, which may block some exploit paths. Clusters that depend solely on Argo's Strict mode are vulnerable. The issue is fixed in versions 3.7.14 and 4.0.5.

An attacker with create Workflow permission can bypass Argo Workflows' templateReferencing: Strict mode, potentially gaining unauthorized host network access, switching service accounts, overriding pod security contexts, scheduling pods on control-plane nodes, and enabling service account token mounting. This can lead to privilege escalation and compromise of cluster security if Kubernetes-level controls are not in place. Clusters relying only on Argo's Strict mode are fully exposed to these risks.

This vulnerability is patched in Argo Workflows versions 3.7.14 and 4.0.5. Users should upgrade to at least these versions to remediate the issue. Additional Kubernetes-level controls such as PodSecurity admission or OPA/Gatekeeper can mitigate some attack vectors independently. Patch status is confirmed by the vendor advisory. No other specific mitigations are indicated.