CVE-2026-6388: argocd-image-updater: ArgoCD Image Updater: Cross-Namespace Privilege Escalation via insufficient namespace validation

Severity: Critical

CVSS Score: 9.1

A flaw was found in ArgoCD Image Updater. This vulnerability allows an attacker, with permissions to create or modify an ImageUpdater resource in a multi-tenant environment, to bypass namespace boundaries. By exploiting insufficient validation, the attacker can trigger unauthorized image updates on applications managed by other tenants. This leads to cross-namespace privilege escalation, impacting application integrity through unauthorized application updates.