Security Testing Methodology

GTP Security Testing Methodology

Comprehensive methodology for testing GTP protocol security across mobile network infrastructures

Testing Objectives

Tunnel Security Assessment

Evaluate GTP tunnel establishment, maintenance, and termination security

Message Integrity Testing

Verify GTP message authentication and integrity mechanisms

Access Control Validation

Test authorization and access control mechanisms

Testing Scope
GTP-C (Control Plane)
GTP-U (User Plane)
GTP' (Charging)
• GGSN/PGW interfaces
• SGSN/SGW interfaces
• MME interfaces
• eNodeB/gNodeB interfaces

Testing Phases

Phase 1: Reconnaissance & Discovery
Identify GTP endpoints and gather network topology information

Network Discovery

  • • Identify GTP-enabled network elements
  • • Map GTP tunnel endpoints
  • • Discover GTP version support
  • • Enumerate supported GTP message types

Traffic Analysis

  • • Capture GTP traffic patterns
  • • Analyze tunnel establishment flows
  • • Identify session management procedures
  • • Document QoS and charging flows
Phase 2: Vulnerability Assessment
Identify potential security weaknesses in GTP implementations

Protocol Analysis

  • • Test message format validation
  • • Analyze sequence number handling
  • • Check tunnel ID management
  • • Verify error handling mechanisms

Security Controls

  • • Authentication mechanism testing
  • • Authorization bypass attempts
  • • Encryption strength assessment
  • • Rate limiting evaluation
Phase 3: Exploitation & Impact Assessment
Demonstrate exploitability and assess potential impact

Attack Execution

  • • GTP tunnel hijacking attempts
  • • Message spoofing and injection
  • • Denial of service testing
  • • Traffic redirection attacks

Impact Analysis

  • • Data confidentiality assessment
  • • Service availability impact
  • • Billing and charging implications
  • • Regulatory compliance effects

Essential Testing Tools

Protocol Analyzers
• Wireshark with GTP dissectors
• tcpdump for packet capture
• Commercial protocol analyzers
Security Testing
• GTPSec testing framework
• Custom packet crafting tools
• Vulnerability scanners
Traffic Generation
• GTP traffic generators
• Load testing tools
• Stress testing utilities