Helm’s plugin verification logic bypasses signature checks when the provenance file (.prov) is missing, allowing unsigned plugins to be installed as if they were legitimate. This flaw permits an attacker to deploy arbitrary code through a malicious plugin that will run with the privileges of the Helm process and can impact the Kubernetes cluster environment.

Helm releases from 4.0.0 through 4.1.3 are affected. The vulnerability was remediated in Helm 4.1.4, which restores proper provenance verification before plugin installation.

The vulnerability carries a CVSS score of 8.4, placing it in the high‑severity range, while its EPSS score is less than 1%, indicating a very low probability of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog. The likely attack vector is inferred from the description: an adversary could supply a plugin without a provenance file; Helm will install and run it as if it were signed, potentially enabling arbitrary code execution under the Helm process with access to the Kubernetes cluster.