CVE-2025-69902: kubectl-mcp-server RCE Vulnerability

CVE-2025-69902 Overview

A command injection vulnerability exists in the minimal_wrapper.py component of kubectl-mcp-server v1.2.0. This security flaw allows attackers to execute arbitrary commands on affected systems by injecting shell metacharacters into user-controlled input. The vulnerability stems from improper input validation in the wrapper component, which fails to adequately sanitize input before passing it to shell commands.

Critical Impact

This command injection vulnerability enables unauthenticated remote attackers to execute arbitrary system commands with the privileges of the kubectl-mcp-server process, potentially leading to complete system compromise, data exfiltration, or lateral movement within Kubernetes environments.

Affected Products

• kubectl-mcp-server v1.2.0
• kubectl-mcp-tool (PyPI package)
• Systems utilizing the minimal_wrapper.py component

Discovery Timeline

• 2026-03-16 - CVE-2025-69902 published to NVD
• 2026-03-17 - Last updated in NVD database

Technical Details for CVE-2025-69902

Vulnerability Analysis

This vulnerability is classified as CWE-94 (Improper Control of Generation of Code, also known as Code Injection). The flaw resides in the minimal_wrapper.py component of kubectl-mcp-server, which provides wrapper functionality for kubectl commands.

The core issue involves insufficient sanitization of user-supplied input before it is incorporated into shell command execution. When attackers inject shell metacharacters (such as ;, |, &&, ||, $(), or backticks) into parameters processed by the wrapper, these characters are interpreted by the underlying shell, allowing arbitrary command execution.

This vulnerability is particularly dangerous in Kubernetes management contexts because the kubectl-mcp-server typically operates with elevated privileges needed to interact with Kubernetes clusters. Successful exploitation could grant attackers the ability to manipulate cluster resources, access secrets, or pivot to other systems within the infrastructure.

Root Cause

The root cause of this vulnerability is the lack of proper input sanitization in the minimal_wrapper.py script before passing user-controlled data to shell execution functions. Python applications commonly introduce command injection vulnerabilities when using functions like os.system(), subprocess.Popen() with shell=True, or similar mechanisms that invoke a shell interpreter without properly escaping or validating input parameters.

The wrapper component fails to implement adequate input validation, allowing shell metacharacters to break out of the intended command context and execute attacker-controlled commands.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker can remotely exploit this vulnerability by crafting malicious input containing shell metacharacters targeted at the minimal_wrapper.py component.

A typical exploitation scenario involves:

1. The attacker identifies an endpoint or interface that processes input through the vulnerable wrapper component
2. The attacker crafts a payload containing shell metacharacters (e.g., ; cat /etc/passwd or $(whoami))
3. The malicious input is passed to the wrapper without sanitization
4. The shell interprets the metacharacters, executing the attacker's injected commands
5. The attacker gains command execution with the privileges of the kubectl-mcp-server process

For detailed technical information on this vulnerability, refer to the AhnLab Security Report and the affected source code on GitHub.

Detection Methods for CVE-2025-69902

Indicators of Compromise

• Unexpected child processes spawned by the kubectl-mcp-server or Python interpreter processes
• Unusual network connections originating from the server hosting kubectl-mcp-server
• Log entries containing shell metacharacters (;, |, &&, $(), backticks) in API requests or command parameters
• Anomalous file system activity or modifications in sensitive directories

Detection Strategies

• Implement application-layer logging to capture all input processed by the minimal_wrapper.py component and analyze for suspicious patterns
• Deploy runtime application self-protection (RASP) solutions to detect and block command injection attempts
• Monitor process creation events for unexpected shell invocations or command sequences spawned by the kubectl-mcp-server process
• Use web application firewalls (WAF) with rules specifically targeting command injection payloads

Monitoring Recommendations

• Enable detailed audit logging for all kubectl-mcp-server interactions and review logs for injection attempt patterns
• Configure alerts for process execution anomalies, particularly shell commands with unusual argument patterns
• Monitor network traffic from kubectl-mcp-server hosts for unexpected outbound connections that may indicate data exfiltration or reverse shells
• Implement file integrity monitoring on critical system files and directories

How to Mitigate CVE-2025-69902

Immediate Actions Required

• Upgrade kubectl-mcp-server to a patched version when available from the vendor
• Restrict network access to the kubectl-mcp-server to trusted sources only using firewall rules or network segmentation
• Implement input validation at the application boundary to reject requests containing shell metacharacters
• Consider temporarily disabling or isolating affected components until a patch is available

Patch Information

Review the kubectl-mcp-server GitHub repository for security updates and patched releases. The PyPI package page should also be monitored for updated versions that address this vulnerability.

Organizations should prioritize applying patches as they become available given the critical severity of this vulnerability and its network-accessible attack vector requiring no authentication.

Workarounds

• Implement a reverse proxy or API gateway with strict input validation to filter shell metacharacters before they reach the vulnerable component
• Run kubectl-mcp-server in an isolated container or sandbox environment with minimal privileges to limit the impact of successful exploitation
• Disable or remove the minimal_wrapper.py component if it is not required for your deployment
• Apply network-level access controls to limit exposure of the vulnerable service to trusted networks only

# Example: Restrict access to kubectl-mcp-server using iptables
# Allow only trusted IP ranges to access the service port
iptables -A INPUT -p tcp --dport 8080 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 8080 -j DROP