Helm's plugin verification fails open when .prov is missing, allowing unsigned plugin install in helm.sh/helm

Open Source Vulnerabilities CVE-2026-35205

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.

Open Source Vulnerabilities BIT-helm-2026-35205

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.

Open Source Vulnerabilities GHSA-q5jf-9vfq-h4h7

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.

Open Source Vulnerabilities GO-2026-5566

Helm's plugin verification fails open when .prov is missing, allowing unsigned plugin install in helm.sh/helm