Code Injection

Category: Command & Code Injection
Severity: Critical
MITRE ATT&CK Mapping: T1059 (Command and Scripting Interpreter)

Description

Injection of malicious code that gets executed within the MCP server environment, enabling attackers to execute arbitrary code and compromise the application runtime.

Technical Details

Attack Vector

  • Dynamic code execution vulnerabilities
  • Script injection attacks
  • Runtime code manipulation
  • Interpreter exploitation

Common Techniques

  • Dynamic code evaluation
  • Script injection
  • Template injection
  • Serialization attacks

Impact

  • Application Compromise: Control over application execution
  • Runtime Manipulation: Modification of application behavior
  • Data Access: Access to application data and memory
  • System Access: Potential system-level access through application

Detection Methods

Code Analysis

  • Monitor dynamic code execution
  • Track script evaluation
  • Detect code injection patterns
  • Analyze code execution flow

Runtime Monitoring

  • Monitor application behavior
  • Track execution patterns
  • Detect runtime anomalies
  • Analyze code execution context

Mitigation Strategies

Code Security

  • Avoid dynamic code execution
  • Use safe evaluation methods
  • Implement code validation
  • Deploy code sandboxing

Runtime Protection

  • Use runtime security controls
  • Implement execution monitoring
  • Deploy code integrity checks
  • Monitor application behavior

Real-World Examples

Example 1: Dynamic Code Evaluation

def execute_formula(formula):
    # Vulnerable dynamic code execution
    result = eval(formula)
    
    # Attack: formula = "__import__('os').system('rm -rf /')"
    # Executed: __import__('os').system('rm -rf /')

Example 2: Template Injection

def generate_report(template, data):
    # Vulnerable template processing
    template_str = f"Result: {template}"
    result = eval(template_str)
    
    # Attack: template = ""
    # Executed: Template injection leading to code execution

Example 3: Serialization Attack

def process_data(serialized_data):
    # Vulnerable deserialization
    data = pickle.loads(serialized_data)
    
    # Attack: serialized_data contains malicious pickled object
    # Executed: Code execution during deserialization

References & Sources

  • Philippe Bogaerts - “The Security Risks of Model Context Protocol (MCP)”
  • Strobes Security - “MCP and Its Critical Vulnerabilities”
  • Structured MCP Threats - Comprehensive threat landscape analysis

Code injection attacks target the application runtime itself, enabling sophisticated attacks that can compromise the entire MCP server environment.