Exposure of Sensitive Information to an Unauthorized Actor
Helm is a tool that streamlines installing and managing Kubernetes applications."getHostByName" is a Helm template function introduced in Helm v3. The function is able to accept a hostname and return an IP address for that hostname. To get the IP address the function performs a DNS lookup. The DNS lookup happens when used with "helm install|upgrade|template" or when the Helm SDK is used to render a chart. Information passed into the chart can be disclosed to the DNS servers used to lookup the IP address. For example, a malicious chart could inject "getHostByName" into a chart in order to disclose values to a malicious DNS server. The vulnerable versions are Helm 3.0.x prior to 3.11.1. Prior to using a chart with Helm verify the "getHostByName" function is not being used in a template to disclose any information you do not want passed to DNS servers.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.