CVE-2026-35205: Helm's plugin verification fails open when .prov is missing, allowing unsigned plugin install

Published Apr 9, 2026
·
Updated

Helm is a package manager for Charts for Kubernetes. From 4.0.0 to 4.1.3, Helm will install plugins missing provenance (.prov file) when signature verification is required. This vulnerability is fixed in 4.1.4.

Other sources

Helm is a package manager for Charts for Kubernetes. In Helm versions >=4.0.0 and <=4.1.3, Helm will install plugins missing provenance (.prov file) when signature verification is required.

Impact

The bug allows plugin authors to omit provenance (signing) data from plugins, bypassing plugin signature verification upon plugin install/update.

Notably, plugin hooks will be executed as designed on the installed plugin, enabling a malicious plugin to execute arbitrary code.

Patches

This issue has been patched in Helm v4.1.4

Installing/updating a plugin with missing provenance will error if signature verification is required.

Workarounds

Users may manually validate that a plugin archive is not missing provenance data (.prov file) before installation.

— GitHub

Affected Software

2 affected componentsFixes available
go/helm.sh/helm/v4>=4.0.0<=4.1.3
4.1.4
Helm helm>=4.0.0<4.1.4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade go/helm.sh/helm/v4 to a version that resolves this vulnerability.

    Fixed in 4.1.4
  2. Upgrade

    Upgrade Helm to a version that resolves this vulnerability.

    Fixed in 4.1.4
  3. Configuration

    Before installing/updating a Helm plugin, verify the plugin archive is not missing provenance data (the .prov file). If .prov is missing, do not proceed with installation/update when signature verification is required.

    Helm plugin installation/signature verification provenance (.prov) presence = required (do not install plugins missing .prov)

Event History

Apr 9, 2026
CVE Published
via MITRE·03:06 PM
Data Sourced
via MITRE·03:06 PM
DescriptionWeakness
Data Sourced
via Red Hat·04:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·04:16 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:16 PM
RemedyAffected Software
Apr 10, 2026
Advisory Published
via GitHub·03:33 PM
Data Sourced
via GitHub·03:33 PM
DescriptionWeaknessAffected Software
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-35205?

CVE-2026-35205 has a moderate severity as it allows for the installation of unsigned plugins when provenance information is missing.

2

How do I fix CVE-2026-35205?

To fix CVE-2026-35205, upgrade to Helm version 4.1.4 or later.

3

What versions of Helm are affected by CVE-2026-35205?

Helm versions from 4.0.0 to 4.1.3 are affected by CVE-2026-35205.

4

What is the nature of the issue in CVE-2026-35205?

CVE-2026-35205 is a vulnerability that allows unsigned plugin installation due to the failure of plugin verification when a .prov file is absent.

5

Is Helm's plugin verification effective in versions before 4.1.4?

No, Helm's plugin verification is ineffective in versions before 4.1.4 because it fails to prevent unsigned plugins from being installed.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203
CVE-2026-35205 - Helm's plugin verification fails open when .prov is missing, allowing unsigned plugin install - SecAlerts