# CVE-2026-35206: Helm path traversal via Chart.yaml name dot-segment

Source: https://junglewise.ai/threats/cve-2026-35206-helm-path-traversal-via-chart-yaml-name-dot-segment  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-09. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2026-35206 · Severity: medium · CVSS 4.4 · Published 2026-04-09

Helm is a package manager used to manage applications on Kubernetes. A vulnerability in how it handles certain package names allows a malicious package to overwrite files in the user's current directory instead of extracting into a new folder. This could lead to the accidental loss or corruption of local configuration files or data when a user downloads and unpacks a specially crafted chart.

Technologies: [helm.sh/helm/v3 (Go)](https://junglewise.ai/threats/technologies/helm-sh-helm-v3), [helm.sh/helm/v4 (Go)](https://junglewise.ai/threats/technologies/helm-sh-helm-v4), [Helm](https://junglewise.ai/threats/technologies/helm). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Helm](https://junglewise.ai/threats/vendors/helm).

## Quick answers

**Is CVE-2026-35206 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35206 being exploited in the wild.

**How severe is CVE-2026-35206?** Medium severity, with a CVSS score of 4.4, published 9 April 2026.

**Which products and versions are affected?** helm.sh/helm/v3 (Go) <= 3.20.1, SEMVER:introduced=0,fixed=3.20.2; helm.sh/helm/v4 (Go) <= 4.1.3, SEMVER:introduced=0,fixed=4.1.4; Helm <= 3.20.1, <= 4.1.3.

**Is there a fix for CVE-2026-35206?** Yes. helm.sh/helm/v3 (Go): upgrade to 3.20.2 or later; helm.sh/helm/v4 (Go): upgrade to 4.1.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-35206 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-35206?** Check whether you run helm.sh/helm/v3 (Go), helm.sh/helm/v4 (Go) or Helm at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- helm.sh/helm/v3 (Go): upgrade to 3.20.2 or later

  ```sh
  go get helm.sh/helm/v3@v3.20.2
  ```

- helm.sh/helm/v4 (Go): upgrade to 4.1.4 or later

  ```sh
  go get helm.sh/helm/v4@v4.1.4
  ```


## Technical details

A path traversal vulnerability (CWE-22) exists in Helm's chart extraction logic. When using 'helm pull --untar', a specially crafted Chart.yaml with a name field containing dot-segments ('.' or '..') can cause the extraction process to 'collapse' the directory structure. Instead of extracting to '<output dir>/<chart name>/', the contents are written directly into '<output dir>/'. While the implementation prevents traversal outside of the designated output directory, it fails to ensure a unique subdirectory is used, allowing an attacker to overwrite existing files within the target destination. This is fixed in Helm v3.20.2 and v4.1.4.

## Affected products

- Helm helm <= 3.20.1, <= 4.1.3

## Identifiers

- CVE-2026-35206
- GHSA-hr2v-4r36-88hr
- GO-2026-5435

## Timeline

- 2026-04-09: disclosed
- 2026-04-09: patched
- 2026-04-10: advisory

## References

- [https://api.github.com/users/1seal](https://api.github.com/users/1seal)
- [https://github.com/1seal](https://github.com/1seal)
- [https://api.github.com/users/1seal/gists%7B/gist_id%7D](https://api.github.com/users/1seal/gists%7B/gist_id%7D)
- [https://api.github.com/users/1seal/repos](https://api.github.com/users/1seal/repos)
- [https://avatars.githubusercontent.com/u/239602944?v=4](https://avatars.githubusercontent.com/u/239602944?v=4)
- [https://api.github.com/users/1seal/events%7B/privacy%7D](https://api.github.com/users/1seal/events%7B/privacy%7D)

## Related threats

- [Helm denial of service in Files.Lines template helper](https://junglewise.ai/threats/cve-2026-63308-helm-denial-of-service-in-files-lines-template-helper)
- [Helm signature verification bypass for plugins missing provenance files](https://junglewise.ai/threats/cve-2026-35205-helm-signature-verification-bypass-for-plugins-missing-provenance)
- [Helm path traversal in plugin metadata version field](https://junglewise.ai/threats/cve-2026-35204-helm-path-traversal-in-plugin-metadata-version-field)
- [GO-2025-3888 - Helm May Panic Due To Incorrect YAML Content in helm.sh/helm](https://junglewise.ai/threats/cve-2025-55198-helm-may-panic-due-to-incorrect-yaml-content)
- [GO-2025-3887 - Helm Charts with Specific JSON Schema Values Can Cause Memory Exhaustion in helm.sh/helm](https://junglewise.ai/threats/cve-2025-55199-helm-charts-with-specific-json-schema-values-can-cause-memory)