Helm Charts with Specific JSON Schema Values Can Cause Memory Exhaustion

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS

• CVE-2025-55199: 0.35% estimated exploitation activity in the next 30 days; percentile 29.21 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

A Helm contributor discovered that it was possible to craft a JSON Schema file in a manner which could cause Helm to use all available memory and have an out of memory (OOM) termination. Impact A malicious chart can point $ref in values.schema.json to a device (e.g. /dev/) or other problem file which could cause Helm to use all available memory and have an out of memory (OOM) termination. Patches This issue has been resolved in Helm v3.18.5. Workarounds Make sure that all Helm charts that are being loaded into Helm doesn't have any reference of $ref pointing to /dev/zero. References Helm's security policy is spelled out in detail in our SECURITY document. Credits Disclosed by Jakub Ciolek at AlphaSense.

Published by the source

14 Aug 2025, 00:01 UTC

Last modified by the source

14 Aug 2025, 17:14 UTC

Source last checked

26 Oct 2026, 15:10 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9h84-qmv7-982p

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# Patch Next advisory brief: CVE-2025-55199

Advisory: Helm Charts with Specific JSON Schema Values Can Cause Memory Exhaustion
IDs: CVE-2025-55199, GHSA-9h84-qmv7-982p
Record: https://patchnext.com/advisories/cve-2025-55199 (revision 1, source checked 26 Oct 2026, 15:10 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: helm.sh/helm/v3 3.18.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go helm.sh/helm/v3: affected < 3.18.5; fixed in 3.18.5

## Suggested inspection (read-only)
- Go helm.sh/helm/v3: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on helm.sh/helm/v3.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9h84-qmv7-982p (GitHub-reviewed advisory GHSA-9h84-qmv7-982p lists affected ranges: Go helm.sh/helm/v3 >=0 <3.18.5)

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