SECTOR: SIGNALING
Security: Signaling - SS7 (Signalling System No. 7)
SS7 is the foundational protocol for mobile roaming and interconnect. Due to its legacy design for a "trusted" environment, it remains a primary vector for location tracking, SMS interception, and fraud.
🛡️ Tactical Domain Mapping: SS7 Security
| Area / Component | Functional Security Objective | ITU Rec (Official PDF) | 3GPP Equiv | 3GPP Target |
|---|---|---|---|---|
| Location Tracking | Peer Authentication & Filtering | Q.1331 | TS 23.003 | Interfaces |
| SMS Interception | Signaling Message Integrity | Q.3062 | TS 23.040 | Security |
| CLI Spoofing | Origin Identity Verification | Q.1331 | TS 24.008 | Architecture |
| Subscriber Profiling | Signaling Obfuscation | X.805 | GSMA FS.11 | Audit |
| Inter-Operator Trust | Cross-Layer Crypto Trust | X.509 | IPsec / mTLS | Interfaces |
🚦 Tactical Release Realizations
For release-specific 3GPP implementations of legacy signaling security, see the generation bridges:
🏛️ Strategic Alignment
- ITU Series: Primarily mapped to itu-t Series-Q (Signaling) and itu-t Series-X (Security Architecture).
- Study Groups: SG11 (Requirements) and SG17 (Security Mitigation).
🧪 Penetration Testing Tools
- s7scan: Protocol-level scanner for SS7 vulnerabilities.
- SigPloit: Telecom signaling pentesting framework.
- SND-Audit: Subscriber Network Data auditing tool.
📋 Field Audit Checklist
[ ]SMS Home Routing: Is SMS Home Routing (GSMA FS.19) implemented to prevent SMS interception?[ ]Category 1/2/3 Filtering: Are the GSMA FS.11 signaling filters active at the STP/GTT?[ ]MAP/CAP Whitelisting: Are Peer SCCP addresses whitelisted for inter-operator interconnect?[ ]GLR (Gateway Location Register): Is a GLR used to minimize the exposure of HSS/HLR data to external peers?[ ]TCAP Handshake: Is the TCAP handshake strictly enforced for all sensitive MAP operations (e.g.,sendRoutingInfo)?
!WARNINGSS7 Vulnerability Awareness: Most SS7 attacks occur at the STP (Signaling Transfer Point) or GTT (Global Title Translation) level where malicious requests are bypassed due to legacy trust configurations.
Last UpdatedJune 5, 2026
ITU-T Navigator v4.0.0
ReferenceITU Recommendation