Report: CVE-2026-39884 - MCP Server Kubernetes has Argument Injection in its port_forward tool via space-

Report: CVE-2026-39884 - MCP Server Kubernetes has Argument Injection in its port_forward tool via space-

CVE ID :CVE-2026-39884 Published : April 14, 2026, 11:25 p.m. | 55 minutes ago Description :mcp-server-kubernetes is a Model Context Protocol server for Kubernetes cluster management. Versions 3.4.0 and prior contain an argument injection vulnerability in the port_forward tool in src/tools/port_forward.ts, where a kubectl command is constructed via string concatenation with user-controlled input and then naively split on spaces before being passed to spawn(). Unlike all other tools in the codebase which correctly use array-based argument passing with execFileSync(), port_forward treats every space in user-controlled fields (namespace, resourceType, resourceName, localPort, targetPort) as an argument boundary, allowing an attacker to inject arbitrary kubectl flags. This enables exposure of internal Kubernetes services to the network by injecting --address=0.0.0.0, cross-namespace targeting by injecting additional -n flags, and indirect exploitation via prompt injection against AI agents connected to the MCP server. This issue has been fixed in version 3.5.0. Severity: 0.0 | NA Visit the link for more details, such as CVSS details, affected products, timeline, and more...

CVE Details

Published
April 14, 2026
Affected Product: kubernetes
Attack Vector: network