SS7 Security Testing Methodology
Structured approach to identifying and exploiting SS7 vulnerabilities
Methodology Overview
Comprehensive view of the SS7 security testing methodology phases
The SS7 security testing methodology provides a structured approach to evaluating the security posture of SS7 networks and identifying vulnerabilities that could be exploited by malicious actors. This methodology is designed for telecommunications security professionals, penetration testers, and network operators responsible for securing SS7 infrastructure.
SS7 (Signaling System No. 7) is a critical protocol suite used in telecommunications networks worldwide for setting up and tearing down calls, SMS delivery, billing, roaming, and other essential services. Originally designed with a focus on reliability rather than security, SS7 networks are vulnerable to various attacks that can lead to location tracking, call interception, SMS interception, service disruption, and fraud.
Important Considerations
- Authorization: Always obtain proper authorization before conducting SS7 security testing
- Legal Compliance: Ensure testing activities comply with relevant laws and regulations
- Risk Management: Implement controls to prevent unintended service disruption
- Confidentiality: Maintain strict confidentiality of all findings and subscriber data
Testing Phases
Key Steps
No steps available for this phase.
Tools & Deliverables
No tools or deliverables available for this phase.
Testing Best Practices
Always obtain proper authorization before conducting SS7 security testing
Use dedicated test environments when possible to avoid production impact
Implement careful controls to prevent unintended service disruption
Document all testing activities in detail for audit purposes
Coordinate testing with network operations teams to ensure proper monitoring
Follow a risk-based approach to prioritize testing efforts
Maintain confidentiality of all findings and subscriber data
Validate findings with multiple tools to reduce false positives
Consider regulatory implications of testing activities
Provide clear, actionable remediation guidance with findings
Test both technical controls and operational procedures
Evaluate detection capabilities alongside prevention measures
SS7 Pentesting Workflow
Detailed workflow for conducting SS7 security assessments
Workflow Stages
Project Initiation
- Define scope and objectives of the SS7 security assessment
- Obtain necessary authorizations and approvals
- Establish communication channels and escalation procedures
- Define success criteria and deliverables
Information Gathering
- Collect network documentation and architecture diagrams
- Identify SS7 network components and interconnections
- Map point codes, global titles, and subscriber ranges
- Document existing security controls and monitoring systems
Vulnerability Assessment
- Analyze network configuration for security weaknesses
- Identify vulnerable SS7 operations and procedures
- Assess implementation of security controls
- Prioritize potential attack vectors based on risk
Exploitation Testing
- Develop and execute test cases for identified vulnerabilities
- Perform controlled exploitation of vulnerabilities
- Document successful attack paths and their impact
- Validate effectiveness of existing security controls
Analysis and Reporting
- Analyze test results and findings
- Assess business impact of identified vulnerabilities
- Develop detailed remediation recommendations
- Prepare comprehensive security assessment report
Remediation Support
- Present findings to stakeholders
- Assist with prioritization of remediation efforts
- Provide technical guidance for implementing security controls
- Validate effectiveness of implemented remediation measures
Documentation & Reporting
Comprehensive documentation and reporting are critical components of the SS7 security testing methodology. Proper documentation ensures that findings are clearly communicated, impacts are understood, and remediation efforts are effectively guided.
Key Report Components
- High-level overview of the assessment
- Summary of critical findings and their business impact
- Risk assessment and prioritization
- Key recommendations for executive stakeholders
- Detailed description of each vulnerability
- Technical impact and exploitation details
- Evidence of successful exploitation
- Affected components and services
- Specific recommendations for each finding
- Implementation guidance for security controls
- Prioritization framework for remediation efforts
- Industry best practices and standards
- Testing methodology details
- Tools and techniques used
- Raw test data and logs
- References and additional resources
Report Templates
Standardized report templates ensure consistency and completeness in documentation. The following templates are recommended for SS7 security assessments:
Executive Report
High-level summary for executive stakeholders
Technical Report
Detailed findings for security teams
Remediation Plan
Structured plan for addressing findings
Tools & Resources
Effective SS7 security testing requires specialized tools and resources. The following tools are commonly used in SS7 security assessments:
SS7 Testing Tools
Reference Resources
Guidelines for implementing security monitoring for SS7 interconnections, helping operators detect and respond to potential attacks.
Comprehensive guidelines for securing SS7 and SIGTRAN networks, including best practices and security controls.
Compliance & Standards
SS7 security testing should align with industry standards and regulatory requirements. The following standards and frameworks are relevant to SS7 security assessments:
The GSMA Security Accreditation Scheme (SAS) provides a framework for assessing the security of mobile network operators and their interconnections, including SS7 networks.
- SAS for UICC Production (SAS-UP)
- SAS for Subscription Management (SAS-SM)
- Network Equipment Security Assurance Scheme (NESAS)
The 3rd Generation Partnership Project (3GPP) develops technical specifications for mobile telecommunications, including security standards for SS7 and related protocols.
- TS 33.200: 3G Security; Network Domain Security (NDS); MAP application layer security
- TS 29.002: Mobile Application Part (MAP) specification
- TS 33.210: Network Domain Security (NDS); IP network layer security
The European Union Agency for Cybersecurity (ENISA) provides recommendations for securing telecommunications networks, including SS7 infrastructure.
- Signalling Security in Telecom SS7/Diameter/5G
- Telecom Security During a Pandemic
- Security Guidance for 5G Implementation
Various regulatory requirements may apply to SS7 security, depending on the jurisdiction and industry sector.
- EU Electronic Communications Code
- FCC Communications Security, Reliability and Interoperability Council (CSRIC)
- National telecommunications regulatory frameworks
Compliance Considerations
When conducting SS7 security assessments, consider the following compliance aspects:
- Data Protection: Ensure compliance with relevant data protection regulations (e.g., GDPR) when handling subscriber data
- Critical Infrastructure: Consider requirements for critical infrastructure protection if applicable
- Telecommunications Regulations: Adhere to telecommunications-specific regulatory requirements
- Reporting Requirements: Be aware of any mandatory reporting requirements for security incidents or vulnerabilities