SMSC Hijacking

In telecommunications, SMSC Hijacking is the abuse of weak interconnect authentication to redirect or inject SMS traffic through an attacker-controlled SMSC, enabling interception of one-time passwords, SMS spoofing, or large-scale spam delivery. SMS Home Routing and SS7 firewalling are key mitigations.

Categories: Core NetworkSignalingRoaming and Interconnect

SMSC Hijacking in context

The mobile core is where subscriber sessions, mobility and policy live. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF. Core exposure is the difference between a single-subscriber leak and a fleet-wide breach.

Signaling protocols carry the control-plane instructions that set up calls, register subscribers, hand over sessions and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA FS.11 / FS.19 / FS.20 as a top-tier telecom risk.

To place SMSC Hijacking in the wider telecom-security picture, review HLR, MAP, SMS Home Routing, GTP-U Smuggling, GGSN and MAP Security.

Related terms

Equipment

Messaging (SMSC, SMS router, MMSC, IP-SM-GW, SMSF, RCS)

Articles in the P1 mobile network security guide

Related topic hubs

  • Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.
  • SS7 Firewall GSMA FS.11 category 1/2/3 SS7 message screening at the STP edge.
  • SMS Firewall SMS spam, phishing, A2P bypass and MAP-layer SMS filtering.
  • Roaming Security IPX/GRX interconnect risk, home-routed vs local-breakout, SEPP.

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.