CVE-2026-40886

Argo Workflows: Unchecked annotation parsing in pod informer crashes Argo Workflows controller

Published Apr 23, 2026 CVSS 3.1 · 7.7 High EPSS < 1% KEV · Not listed
Description
Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. From 3.6.5 to 4.0.4, an unchecked array index in the pod informer's podGCFromPod() function causes a controller-wide panic when a workflow pod carries a malformed workflows.argoproj.io/pod-gc-strategy annotation. Because the panic occurs inside an informer goroutine (outside the controller's recover() scope), it crashes the entire controller process. The poisoned pod persists across restarts, causing a crash loop that halts all workflow processing until the pod is manually deleted. This vulnerability is fixed in 4.0.5 and 3.7.14.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-5jv8-h7qh-rf5p Argo Workflows: Unchecked annotation parsing in pod informer crashes Argo Workflows Controller
History
Type Values Removed Values Added
First Time appeared Argoproj argo Workflows
CPEs cpe:2.3:a:argoproj:argo_workflows:*:*:*:*:*:go:*:*
Vendors & Products Argoproj argo Workflows
Type Values Removed Values Added
First Time appeared Argoproj
Argoproj argo-workflows
Vendors & Products Argoproj
Argoproj argo-workflows
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. From 3.6.5 to 4.0.4, an unchecked array index in the pod informer's podGCFromPod() function causes a controller-wide panic when a workflow pod carries a malformed workflows.argoproj.io/pod-gc-strategy annotation. Because the panic occurs inside an informer goroutine (outside the controller's recover() scope), it crashes the entire controller process. The poisoned pod persists across restarts, causing a crash loop that halts all workflow processing until the pod is manually deleted. This vulnerability is fixed in 4.0.5 and 3.7.14.
Title Argo Workflows: Unchecked annotation parsing in pod informer crashes Argo Workflows controller
Weaknesses CWE-129
References
Metrics cvssV3_1

{'score': 7.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 15, 2026, 1:00 AM
Reserved
Apr 15, 2026, 3:57 PM
Status
Modified
Published
Apr 23, 2026, 7:17 PM
Modified
Oct 26, 2026, 10:10 PM
Severity
Important
Public date
Apr 23, 2026, 6:12 PM