In Helm from version 3.0 and before version 3.5.2, there a few cases where data loaded from potentially untrusted sources was not properly sanitized. When a SemVer in the `version` field of a chart is invalid, in some cases Helm allows the string to be used "as is" without sanitizing. Helm fails to properly sanitize some fields present on Helm repository `index.yaml` files. Helm does not properly sanitize some fields in the `plugin.yaml` file for plugins In some cases, Helm does not properly sanitize the fields in the `Chart.yaml` file. By exploiting these attack vectors, core maintainers were able to send deceptive information to a terminal screen running the `helm` command, as well as obscure or alter information on the screen. In some cases, we could send codes that terminals used to execute higher-order logic, like clearing a terminal screen. Further, during evaluation, the Helm maintainers discovered a few other fields that were not properly sanitized when read out of repository index files.
External References: https://github.com/helm/helm/commit/6ce9ba60b73013857e2e7c73d3f86ed70bc1ac9a https://github.com/helm/helm/releases/tag/v3.5.2 https://github.com/helm/helm/security/advisories/GHSA-c38g-469g-cmgx