---
title: "CVE-2026-61459: mcp-server-kubernetes argument injection can expose Kubernetes cluster credentials"
url: https://erroneo.us/security/cve/CVE-2026-61459/
description: "CVE-2026-61459 (mcp-server-kubernetes (PyPI)): MCP Server Kubernetes before 3.9.0 contains an argument injection vulnerability in structured tools…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-10
date_modified: 2026-08-12
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-61459"
kev: false
cvss: 9.3
epss: 0.02362
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-61459: mcp-server-kubernetes argument injection can expose Kubernetes cluster credentials

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 2.4% , percentile 84: FIRST’s model estimates a 2.4% chance of exploitation activity in the next 30 days, higher than 84% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes mcp-server-kubernetes (PyPI) < 3.9.0, fixed in 3.9.0 . Check your lockfile, including transitive dependencies.

## What it is

MCP Server Kubernetes before 3.9.0 contains an argument injection vulnerability in structured tools (kubectlget, kubectldescribe, kubectldelete) that allows attackers to bypass the assertNoDangerousFlags security check by supplying resourceType and name parameters with leading dashes. Attackers can inject the --server flag to redirect kubectl commands to an attacker-controlled API server, causing the operator's bearer token to be transmitted externally and enabling full cluster compromise.

## Affected packages

- PyPI `mcp-server-kubernetes` < 3.9.0 → fixed: 3.9.0

## Affected products (CVE record)

- Flux159 mcp-server-kubernetes: < 3.9.0

## Severity

- VulnCheck CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
- VulnCheck CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 2.36% probability of exploitation activity in the next 30 days; percentile 84.

## Sources

- [Release Notes](https://github.com/Flux159/mcp-server-kubernetes/releases/tag/3.9.0)
- [Patch Commit](https://github.com/Flux159/mcp-server-kubernetes/commit/d7890f50a4567bf5d9842541ba6f41e180227f9a)
- [GitHub Advisory GHSA-wmg3-h8mf-wgvr](https://github.com/advisories/GHSA-wmg3-h8mf-wgvr)
- [CVE.org record CVE-2026-61459](https://www.cve.org/CVERecord?id=CVE-2026-61459)
- [NVD entry CVE-2026-61459](https://nvd.nist.gov/vuln/detail/CVE-2026-61459)
- [Researcher Disclosure](https://github.com/Flux159/mcp-server-kubernetes/issues/328)
- [Pull Request](https://github.com/Flux159/mcp-server-kubernetes/pull/329)
- [vulncheck.com](https://www.vulncheck.com/advisories/mcp-server-kubernetes-argument-injection-via-kubectl-structured-tools)

---
Source page: https://erroneo.us/security/cve/CVE-2026-61459/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt