GHSA-q5jf-9vfq-h4h7
Helm's plugin verification fails open when .prov is missing, allowing unsigned plugin install
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | helm.sh/helm/v4 | >= 4.0.0, < 4.1.4 | 4.1.4 |
Details
As written in the advisory (Markdown source, shown as plain text).
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.
References
External links from the advisory. They lead to third-party sites.
- https://github.com/helm/helm/security/advisories/GHSA-q5jf-9vfq-h4h7
- https://nvd.nist.gov/vuln/detail/CVE-2026-35205
- https://github.com/helm/helm/commit/05fa37973dc9e42b76e1d2883494c87174b6074f
- https://github.com/helm/helm
- https://github.com/helm/helm/releases/tag/v4.1.4
- https://helm.sh/docs/topics/provenance/#the-provenance-file