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[ CVE-2026-77459 · Published 13 Oct 2026 ]

Argo CD: AppProject destination-namespace and resource restrictions bypassed by PreDelete/PostDelete resource hooks

CVSS 9.9 EPSS <1%1 agency advisoryFix available

[ Why it matters ]Priority signals

  • Critical severity: CVSS 9.9

[ Description ]Official description

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. From 2.10.0 until 3.3.15, 3.4.10, 3.5.4, and 3.6.0-rc2, Argo CD creates PostDelete resource hooks without applying the AppProject destination and resource authorization checks used during ordinary synchronization. The omitted checks include cluster-scoped and namespaced resource allow/deny lists. A user who can write to an Application's Git repository can commit a delete hook targeting a forbidden namespace, server, group, kind, or resource name, and deletion of the Application causes the application-controller to create that resource with its destination-cluster credentials. The reachable impact is bounded by the controller's cluster access but can include cluster-scoped resources, disallowed namespaces, persistent hook objects, and secondary objects created by a hook Job. PreSync, Sync, PostSync, and SyncFail hooks continue to use the normal project checks. This issue is fixed in versions 3.3.15, 3.4.10, 3.5.4, and 3.6.0-rc2.

[ Fixes ]Fixes and patches

[ Advisories ]Government CERT advisories

[ Packages ]Affected open-source packages

  • github.com/argoproj/argo-cd/v2 goAffected >= 2.10.0, <= 2.14.21 · GHSA-fmxq-cgp8-87wp
  • github.com/argoproj/argo-cd/v3 goAffected >= 3.0.0, < 3.3.15 · fixed in 3.3.15 · GHSA-fmxq-cgp8-87wp
  • github.com/argoproj/argo-cd/v3 goAffected >= 3.4.0, < 3.4.10 · fixed in 3.4.10 · GHSA-fmxq-cgp8-87wp
  • github.com/argoproj/argo-cd/v3 goAffected >= 3.5.0, < 3.5.4 · fixed in 3.5.4 · GHSA-fmxq-cgp8-87wp
  • github.com/argoproj/argo-cd/v3 goAffected >= 3.6.0-rc1, < 3.6.0-rc2 · fixed in 3.6.0-rc2 · GHSA-fmxq-cgp8-87wp

[ References ]References