CVE-2026-47250

mcp-server-kubernetes: kubectl-generic flag injection enables Kubernetes bearer token exfiltration

Published Jun 11, 2026 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-6mx4-4h42-r8vh MCP Server Kubernetes: kubectl-generic flag injection enables Kubernetes bearer token exfiltration
History
Type Values Removed Values Added
First Time appeared Flux159
Flux159 mcp-server-kubernetes
Vendors & Products Flux159
Flux159 mcp-server-kubernetes
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title mcp-server-kubernetes: kubectl-generic flag injection enables Kubernetes bearer token exfiltration
Weaknesses CWE-88
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 11, 2026, 7:35 PM
Reserved
May 18, 2026, 10:54 PM
Status
Deferred
Published
Jun 11, 2026, 7:16 PM
Modified
Oct 26, 2026, 11:10 AM