Vulnerability in Argoproj Argo-Workflows
CVE-2026-40886
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.
EPSS: 0.004 (30.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Argoproj Argo-workflows — versions >= 4.0.0, < 4.0.5, >= 3.7.0, < 3.7.14, >= 3.6.5, <= 3.6.19
- Argoproj Argo_workflows
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-40886?
- CVE-2026-40886 is a high-severity vulnerability in Argoproj Argo-Workflows, classified under Improper Validation of Array Index. CVSS score: 7.7/10. Published 2026-04-23.
- How severe is CVE-2026-40886?
- High severity. CVSS v3 base score is 7.7 out of 10.