CVE-2026-39884: mcp-server-kubernetes is a Model Context Protocol server for Kubernetes cluster management. Versions 3.4.0 and prior con

mcp-server-kubernetes versions 3.4.0 and earlier have an argument injection vulnerability (a type of attack where an attacker sneaks extra commands into a tool by exploiting how input is processed) in the port_forward tool. The vulnerability exists because the code builds a kubectl command (a tool for managing Kubernetes clusters) by concatenating strings with user input and splitting on spaces, instead of using a safer array-based method like other tools in the codebase. This allows attackers to inject malicious kubectl flags to expose internal services or target resources in unintended ways.