CVE-2026-35206 — helm
Fix: helm/helm@4e7994dCVE-2026-35206 is a Path Traversal vulnerability in helm.sh/helm/v4. A fix is available for helm.sh/helm/v4 — see the affected versions and patch details below.
Helm Chart extraction output directory collapse via `Chart.yaml` name dot-segment
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-35206.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
helm.sh/helm/v4🐹helm.sh/helm/v3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Helm is a package manager for Charts for Kubernetes. In Helm versions <=3.20.1 and <=4.1.3, a specially crafted Chart will cause helm pull --untar [chart URL | repo/chartname] to write the Chart's contents to the immediate output directory (as defaulted to the current working directory; or as given by the --destination and --untardir flags), rather than the expected output directory suffixed by the chart's name.
Impact
The bug enables writing the Chart's contents (unpackaged/untar'ed) to the output directory <output dir>/, instead of the expected <output dir>/<chart name>/, potentially overwriting the contents of the targeted directory.
Note: a chart name containing POSIX dot-dot, or dot-dot and slashes (as if to refer to parent directories) do not resolve beyond the output directory as designed.
Patches
This issue has been resolved in Helm v3.20.2 and v4.1.3
A Chart with an unexpected name (those specified to be "." or ".."), or a Chart name which results in a non-unique directory will be rejected.
Workarounds
Ensure the the name of the Chart does not comprise/contain POSIX pathname special directory references ie. dot-dot ("..") or dot ("."). In addition, ensuring that the pull --untar flag (or equivalent SDK option) refers to a unique/empty output directory prevents chart extraction from inadvertently overwriting existing files within the specified directory.
Credits
Oleh Konko @1seal
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | helm.sh/helm/v4 | all versions | 4.1.4go get helm.sh/helm/v4@v4.1.4 |
| 🐹Go | helm.sh/helm/v3 | all versions | 3.20.2go get helm.sh/helm/v3@v3.20.2 |
Affected Products
helmhelmDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for helm.sh/helm/v4, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update helm.sh/helm/v4 to 4.1.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-35206 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Helm CLI 4.1 | helm-cli-4.1.4 | RHSA-2026:26441 |
| multicluster engine for Kubernetes 2.8 | multicluster-engine/backplane-rhel9-operator:1782476869 | RHSA-2026:30650 |
| Red Hat Advanced Cluster Management for Kubernetes 2.13 | rhacm2/multicloud-integrations-rhel9:1782256081 | RHSA-2026:30651 |
Frequently Asked Questions
Is CVE-2026-35206 in your dependencies?
Find it across Go, including transitive dependencies.