External risk intelligence

Argo CD Helm Integration Vulnerability Allows Repository Data Exposure

CVE advisorySeverity: CRITICAL (CVSS 9.9)

CVE-2026-113709

Argo CD is a continuous delivery tool deployed in Kubernetes environments. While it often includes an API and web interface, this specific vulnerability requires a non-default configuration (enabling --enable-helm) and authenticated access to an Application. Because it is typically managed within internal infrastructure and requires specific setup choices, public internet reachability is possible but not guaranteed for all deployments.

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory concerns a critical vulnerability in Argo CD, a tool used for continuous delivery in Kubernetes environments. The issue arises when a specific configuration option is enabled, allowing specially crafted files to execute unauthorized code within the system. This could lead to the exposure of sensitive repository credentials and other process-accessible data. The primary risk requires a specific operator enablement and authenticated access, meaning not all deployments are inherently vulnerable.

Malicious files can execute code in our delivery tool.
It allows unauthorized access to repository secrets.
Confirm if the specific feature is enabled.

Attack Path

How an attacker could exploit the issue

An attacker could compromise Argo CD deployments by embedding malicious Helm downloader plugins within a Git repository or uploading them via an API. This requires the `--enable-helm` option to be active, allowing Helm to load plugins from a repository-controlled location. If an Argo CD Application builds from such a repository or uses the `manifestsWithFiles` API, the malicious plugin can execute as the repo-server user, potentially exposing sensitive credentials.

Requires `--enable-helm` to be configured.
Triggered by building from a malicious repository.
Risk of credential exposure and data access.

Live Threat

Current exploitation, exposure, and threat context

When Argo CD's Helm support is enabled for Kustomize builds, a malicious configuration committed to a Git repository or uploaded via API could cause the repository server to execute arbitrary code. This execution, running as the repo-server user, could expose sensitive data accessible to that user, such as repository credentials. This attack requires specific prior operator configuration and authenticated access to an existing Application resource.

Repository credentials could be exposed.
Arbitrary code execution may occur.
Sensitive data access is a risk.

Operational Fix

Recommended remediation, mitigation, and detection steps

Application and platform teams are likely responsible for addressing this vulnerability in Argo CD, especially in Kubernetes environments where it's deployed. The initial step involves identifying all instances of Argo CD where the `--enable-helm` Kustomize build option is active, assessing their reachability and criticality, and then locating the specific application or system owners to plan a coordinated remediation.

Platform and application teams own resolution.
Verify `--enable-helm` Kustomize builds are active.
Plan and execute remediation within maintenance windows.

Supplementary metadata

CVSS vector

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Frequently asked questions

What is Argo CD and why is it used?

Argo CD is a GitOps continuous delivery tool that automates the deployment of applications into Kubernetes clusters. It tracks changes in a Git repository and keeps the live state of your cluster in sync with the desired configuration. By continuously monitoring repositories, it simplifies managing complex application lifecycles and ensures consistency across environments.

What is the weakness class for CVE-2026-113709?

This vulnerability is classified as CWE-829, which refers to the inclusion of functionality from an untrusted control sphere. In plain terms, it means the software trusts and executes code or plugins fetched from a location that an attacker can control. In this specific case, Argo CD mistakenly allows Helm to load and run unauthorized downloader plugins hidden within a repository, giving that malicious code the same permissions as the underlying repo-server process.

How can an attacker trigger this vulnerability?

An attacker needs to commit a malicious plugin and configuration to a Git repository or upload them via the application API. Critically, this only works if the operator has enabled the --enable-helm option for Kustomize builds. If you have not enabled this specific configuration, your system is not vulnerable to this attack path, as the mechanism that misinterprets the plugin directory remains inactive.

Is my instance at risk according to Halo Surface Signal?

Halo Surface Signal identifies this as a potential risk, noting that while Argo CD is often internal, public reachability is possible. You should care if your deployment uses the --enable-helm setting, as this expands the attack surface. Since the flaw requires authenticated access to an existing Application, securing your API access and reviewing which users have permissions to manage Application resources is a key part of limiting your exposure.

Do I need to update my software to fix this?

Yes, you should plan to move to a patched version, which includes 3.3.15, 3.4.10, 3.5.4, or 3.6.0-rc2. Before patching, check if your configuration has the --enable-helm Kustomize build option active. If you use this feature, prioritize updating your Argo CD installation to prevent the repository server from executing unauthorized plugins. Coordinate with your platform team to schedule this update within your maintenance windows.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.