GTP-C Spoofing

In telecommunications, GTP-C Spoofing is the forging of GTP control-plane messages (Create Session Request, Delete Session Request, Modify Bearer) on S5/S8/S11 or N4/N11-equivalent interfaces to hijack subscriber sessions, exhaust bearer resources, or trigger billing anomalies. Mitigation relies on GTP firewalls validating source PLMN, IMSI ranges, and TEID consistency.

Categories: Radio Access NetworkSignalingIdentity and Subscriber

GTP-C Spoofing in context

The radio access network is where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations and downgrade attacks; defenses rest on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

Signaling protocols carry the control-plane messages that set up calls, register subscribers 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 as top-tier telecom risk.

To place GTP-C Spoofing in the wider telecom-security picture, review BTS Impersonation (Fake BTS), Cleartext (Plain Text), E911, OFCS, Rogue Base Station (Fake BTS) and SMS Pumping — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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