CVE-2026-54526Argo Workflows: Incomplete fix for CVE-2026-31892: ArtifactGC.PodSpecPatch bypass of Strict/Secure templateReferencing

Description

Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. Prior to 3.7.15 and 4.0.6, the allow-list fix for CVE-2026-31892 is incomplete because workflow/util/merge.go ValidateUserOverrides and SanitizeUserWorkflowSpec walk only the top-level fields of WorkflowSpec via reflection, and WorkflowSpec.ArtifactGC is allow-listed wholesale; the struct behind that field, WorkflowLevelArtifactGC, has a PodSpecPatch sub-field whose contents flow unmodified into util.ApplyPodSpecPatch on the artifact-GC pod, the same sink the original fix closed for WorkflowSpec.PodSpecPatch, so a user submitting a Workflow under templateReferencing: Strict or Secure (against a referenced WorkflowTemplate that declares an output artifact and setting spec.artifactGC.strategy: OnWorkflowCompletion) can still inject an arbitrary strategic merge patch into the artifact-GC pod, including hostPath volumes, privileged: true, arbitrary image and command, and hostNetwork: true, defeating the stated purpose of Strict/Secure reference mode. This issue is fixed in versions 3.7.15 and 4.0.6.

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

References and patches

• https://github.com/argoproj/argo-workflows/security/advisories/GHSA-48p8-g2fx-3wwm ExploitVendor Advisory
• https://github.com/argoproj/argo-workflows/commit/277e9cef0ad16d7eaaab253573d0695951a65dbd Patch
• https://github.com/argoproj/argo-workflows/commit/358cc3968c8f06f1be0967e41df191088db0b662 Patch
• https://github.com/argoproj/argo-workflows/releases/tag/v3.7.15 ProductRelease Notes
• https://github.com/argoproj/argo-workflows/releases/tag/v4.0.6 ProductRelease Notes