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.
Affected products
argoproj: argo workflows
References5
- github.com/argoproj/argo-workflows/security/advisories/GHSA-5jv… ExploitVendor Advisory
- github.com/argoproj/argo-workflows/security/advisories/GHSA-5jv… ExploitVendor Advisory
- access.redhat.com/security/cve/CVE-2026-40886
- bugzilla.redhat.com/show_bug.cgi?id=2461236
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40886…
Metrics
- CVSS 3.1
-
7.7
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 32 · as of 13 November 2026
- CWE
- CWE-129CWE-1285
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.