Helm's Missing YAML Content Leads To Panic

A Helm contributor discovered uninitialized variable vulnerability when Helm parses index and plugin yaml files missing expected content.

Impact

When either an index.yaml file or a plugins plugin.yaml file were missing all metadata a panic would occur in Helm.

In the Helm SDK this is found when using the LoadIndexFile or DownloadIndexFile functions in the repo package or the LoadDir function in the plugin package. For the Helm client this impacts functions around adding a repository and all Helm functions if a malicious plugin is added as Helm inspects all known plugins on each invocation.

Patches

This issue has been resolved in Helm v3.14.2.

Workarounds

If a malicious plugin has been added which is causing all Helm client commands to panic, the malicious plugin can be manually removed from the filesystem.

If using Helm SDK versions prior to 3.14.2, calls to affected functions can use recover to catch the panic.

For more information

Helm’s security policy is spelled out in detail in our SECURITY document.

Credits

Disclosed by Jakub Ciolek at AlphaSense.