CVE-2025-32387: Helm Allows A Specially Crafted JSON Schema To Cause A Stack Overflow
A Helm contributor discovered that a specially crafted JSON Schema within a chart can lead to a stack overflow.
Impact A JSON Schema file within a chart can be crafted with a deeply nested chain of references, leading to parser recursion that can exceed the stack size limit and trigger a stack overflow.
Patches This issue has been resolved in Helm v3.17.3.
Workarounds Ensure that the JSON Schema within any charts loaded by Helm does not have a large number of nested references. These JSON Schema files are larger than 10 MiB.
For more information Helm's security policy is spelled out in detail in our SECURITY document.
Credits Disclosed by Jakub Ciolek at AlphaSense.
Other sources
Helm Allows A Specially Crafted JSON Schema To Cause A Stack Overflow
— Microsoft
Helm is a package manager for Charts for Kubernetes. A JSON Schema file within a chart can be crafted with a deeply nested chain of references, leading to parser recursion that can exceed the stack size limit and trigger a stack overflow. This issue has been resolved in Helm v3.17.3.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-32387?
CVE-2025-32387 has a high severity due to the potential for a stack overflow caused by deeply nested references.
How do I fix CVE-2025-32387?
To fix CVE-2025-32387, update Helm to version 3.17.3 or later.
What causes CVE-2025-32387?
CVE-2025-32387 is caused by a JSON Schema file within a chart being crafted with excessive nested references.
Which versions of Helm are affected by CVE-2025-32387?
Helm versions prior to 3.17.3 are affected by CVE-2025-32387.
Is there a workaround for CVE-2025-32387?
There are no known workarounds for CVE-2025-32387 other than upgrading to the patched version.