CVE-2026-25546: Critical Command Injection Flaw in Godot MCP Enables Remote Code Execution on Developer Systems

Vulnerability Overview

CVE ID: CVE-2026-25546
Affected Component: Godot MCP (Model Context Protocol server for Godot)
Affected Versions: All versions below 0.1.1
Vulnerability Type: OS Command Injection
Impact: Remote Code Execution (RCE)
CVSS v3.1 Score: 7.8
Severity: High
Exploitability: Low complexity, high impact
Exploit Availability: Public proof-of-concepts are available for educational and research purposes

Description

A command injection vulnerability was identified in the Godot MCP server prior to version 0.1.1. The issue existed due to unsafe handling of user-supplied input that was passed directly into operating system command execution logic.

Within the MCP server, certain operations required interaction with the local Godot binary. To perform these actions, system commands were dynamically constructed using parameters such as projectPath. These parameters were not properly validated or sanitized before being executed through a shell-based command execution method.

Because the command execution mechanism relied on shell interpretation, specially crafted input containing shell metacharacters could alter the intended command flow. As a result, arbitrary system commands could be executed with the same privileges as the MCP service.

Affected Attack Surface

The vulnerability could be triggered through MCP operations that internally invoke system commands, including but not limited to:

Project creation or loading actions
Scene or asset manipulation requests
Operations that require querying or validating the Godot editor binary

Any interface capable of supplying crafted input to these operations could potentially be abused if the MCP service was reachable.

Impact Analysis

If successfully exploited, the following impacts were possible:

Execution of arbitrary operating system commands
Full compromise of the host running the MCP server
Unauthorized access to source code, credentials, or local files
Potential lateral movement within development or CI environments

Because MCP servers are often executed on developer workstations or build systems, exploitation could lead to broader supply-chain or intellectual-property risks.

Root Cause

The root cause was the use of shell-based command execution with untrusted input. Specifically:

User-controlled parameters were concatenated into command strings
The execution method invoked a system shell
No strict validation or escaping was applied

This combination allowed shell metacharacters to be interpreted by the operating system rather than treated as literal data.

Exploitability and PoC Status

Public proof-of-concept material demonstrating exploitation of this vulnerability has been published.

Due to the straightforward nature of the flaw and the availability of example exploits, the likelihood of abuse in unpatched environments was considered realistic, particularly in exposed or shared development setups.

MITRE Classification

CWE: CWE-78 – Improper Neutralization of Special Elements used in an OS Command
ATT&CK Techniques:
- T1059 – Command and Scripting Interpreter
- T1204 – User Execution (context-dependent)

Detection Guidance

Log Sources

The following log sources should be enabled and monitored:

Endpoint Detection and Response (EDR) telemetry
Process creation logs (Windows, Linux, macOS)
Application logs from the MCP service
System audit logs (auditd, Windows Event Logs)

Detection Queries

Splunk

index=process_logs
(process_name="node" OR process_name="godot-mcp")
| where like(command_line,"%&%") OR like(command_line,"%|%") OR like(command_line,"%$()%") OR like(command_line,"%`%")
| stats count by host, user, process_name, command_line

Elastic / KQL

process.name : ("node" or "godot-mcp") and
process.command_line : ("*&*" or "*|*" or "*$()*" or "*`*")

Microsoft Defender / Advanced Hunting (KQL)

DeviceProcessEvents
| where FileName in ("node.exe", "godot-mcp.exe")
| where ProcessCommandLine has_any (";", "|", "$(", "`")
| project Timestamp, DeviceName, FileName, ProcessCommandLine, InitiatingProcessAccountName

Behavioral Indicators

MCP or Node.js processes spawning shells (sh, bash, cmd.exe, powershell.exe)
Unexpected child processes such as network utilities or scripting engines
Unusual outbound network activity immediately following MCP operations
Suspicious characters embedded in project path or operation parameters

Mitigation and Remediation

Primary Remediation

The vulnerability has been fully addressed in version 0.1.1 of Godot MCP. The fix removes shell-based execution and replaces it with safer execution methods that do not interpret user input through a shell.

Official Patch / Upgrade Link:
https://github.com/Coding-Solo/godot-mcp/commit/21c785d923cfdb471ea60323c13807d62dfecc5a

Upgrading to this version or later fully mitigates the issue.

Additional Hardening Recommendations

Restrict MCP service exposure to trusted local clients only
Run the service under a low-privileged operating system account
Apply application allow-listing where feasible
Monitor and alert on abnormal process execution chains
Review and audit all MCP integrations and access paths

Post-Remediation Validation

After upgrading:

Confirm that no shell-based execution is performed by the MCP service
Validate that user-supplied parameters are passed strictly as arguments
Re-run detection queries to ensure no anomalous activity persists

Final Takeaway

CVE-2026-25546 represented a high-impact command injection flaw within Godot MCP that could lead to full system compromise if left unpatched. Due to the availability of public educational proof-of-concepts and the simplicity of exploitation, immediate remediation was strongly required.

Applying the official update to version 0.1.1 or later effectively eliminates the vulnerability and is the recommended course of action for all users of the affected software.