In Helm greater than or equal to 3.0.0 and less than 3.2.4, a path traversal attack is possible when installing Helm plugins from a tar archive over HTTP. It is possible for a malicious plugin author to inject a relative path into a plugin archive, and copy a file outside of the intended directory. This has been fixed in 3.2.4.
In Helm before versions 2.16.11 and 3.3.2, a Helm plugin can contain duplicates of the same entry, with the last one always used. If a plugin is compromised, this lowers the level of access that an attacker needs to modify a plugin's install hooks, causing a local execution attack. To perform this attack, an attacker must have write access to the git repository or plugin archive (.tgz) while being downloaded …
In Helm before versions 2.16.11 and 3.3.2 plugin names are not sanitized properly. As a result, a malicious plugin author could use characters in a plugin name that would result in unexpected behavior, such as duplicating the name of another plugin or spoofing the output to helm –help. This issue has been patched in Helm 3.3.2. A possible workaround is to not install untrusted Helm plugins. Examine the name field …