{"cve":"CVE-2021-21303","nvd":{"published":"2021-02-05T22:15:12.640","modified":"2026-06-17T03:35:15.167","status":"Modified","description":"Helm is open-source software which is essentially \"The Kubernetes Package Manager\". Helm is a tool for managing Charts. Charts are packages of pre-configured Kubernetes resources. 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 sanitized some fields present on Helm repository `index.yaml` files. Helm does not properly sanitized 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. This fix remedies all such cases, and once again enforces SemVer2 policies on version fields. All users of the Helm 3 should upgrade to the fixed version 3.5.2 or later. Those who use Helm as a library should verify that they either sanitize this data on their own, or use the proper Helm API calls to sanitize the data.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N","score":6.8},"cwes":["CWE-74"],"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","https://github.com/helm/helm/commit/6ce9ba60b73013857e2e7c73d3f86ed70bc1ac9a","https://github.com/helm/helm/releases/tag/v3.5.2"],"products":["helm:helm"],"source":"nvd","synced_at":"2026-10-19T21:14:10.479542811+00:00"},"epss":{"cve":"CVE-2021-21303","score":0.01086,"percentile":0.65296,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-c38g-469g-cmgx","url":"https://osv.dev/vulnerability/GHSA-c38g-469g-cmgx","summary":"Improper Neutralization of Special Elements in Output in helm.sh/helm/v3","modified":"2026-07-08T06:27:57.157120110Z","packages":[{"ecosystem":"Go","name":"helm.sh/helm/v3","purl":"pkg:golang/helm.sh/helm/v3","ranges":[">=3.0.0 <3.5.2"],"fixed":["3.5.2"]}]},{"id":"GO-2022-1040","url":"https://osv.dev/vulnerability/GO-2022-1040","summary":"Insufficient sanitization of data files in helm.sh/helm/v3","modified":"2024-05-20T16:03:47Z","packages":[{"ecosystem":"Go","name":"helm.sh/helm/v3","purl":"pkg:golang/helm.sh/helm/v3","ranges":[">=3.0.0 <3.5.2"],"fixed":["3.5.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}