# CVE-2026-61459: MCP Server Kubernetes < 3.9.0 Argument Injection via kubectl Structured Tools

> Attackers can inject arguments into kubectl tools to steal bearer tokens and compromise the Kubernetes cluster.

- **Severity:** Critical 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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** GHSA-wmg3-h8mf-wgvr, PYSEC-2026-3685

## What is CVE-2026-61459?

CVE-2026-61459 is a critical command injection vulnerability in Flux159 mcp-server-kubernetes, published on 10 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

MCP Server Kubernetes before 3.9.0 contains an argument injection vulnerability in structured tools (kubectl_get, kubectl_describe, kubectl_delete) 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.

Weakness: CWE-88 (Improper Neutralization of Argument Delimiters in a Command)

## Which versions are affected by CVE-2026-61459?

3 open source packages ship an affected version, including mcp-server-kubernetes. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mcp-server-kubernetes` | PyPI | All versions | 3.9.0 |
| `mcp-server-kubernetes` | npm | All versions | 3.9.0 |
| `mcp-server-kubernetes` | npm | All versions | 3.9.0 |

Products: Suyogs Mcp-Server-Kubernetes.

## How do I fix CVE-2026-61459?

Upgrade mcp-server-kubernetes to 3.9.0 or later.

## Is CVE-2026-61459 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-61459 exists.

Public exploit code:

- mcp-server-kubernetes 3.8.x - Argument Injection (exploitdb)

## Other vulnerabilities in Flux159 mcp-server-kubernetes

- [CVE-2026-39884](https://insights.sbomify.com/CVE-2026-39884/): MCP Server Kubernetes has Argument Injection in its port_forward tool via space-splitting (high 8.3)
- [CVE-2025-66404](https://insights.sbomify.com/CVE-2025-66404/): mcp-server-kubernetes potential security issue in exec_in_pod tool (medium 6.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-61459 and fix it if it is affected.

What it is: CVE-2026-61459 is a critical command injection vulnerability in Flux159 mcp-server-kubernetes, published on 10 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-61459 exists.

Affected packages and fixed versions:
- mcp-server-kubernetes (PyPI): affected all versions; fixed in 3.9.0
- mcp-server-kubernetes (npm): affected all versions; fixed in 3.9.0
- mcp-server-kubernetes (npm): affected all versions; fixed in 3.9.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-61459/ (Markdown: https://insights.sbomify.com/CVE-2026-61459/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-61459
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-61459
- OSV: https://osv.dev/vulnerability/CVE-2026-61459

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-61459/
Summaries are generated and may contain mistakes; the official description above is the record.