Grey Route SMS (Grey-Route SMS)

A grey-route SMS is an application-to-person (A2P) message delivered to a mobile subscriber via a path that bypasses the terminating operator's commercial A2P agreement — typically SIM-farm P2P injection, SS7 MAP MO-ForwardSM abuse, or misdeclared traffic — depriving the operator of revenue and undermining anti-spam controls.

Categories: SignalingIdentity and SubscriberFraud

Grey Route SMS in context

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.

Subscriber identifiers (IMSI, SUPI, MSISDN, IMEI) anchor authentication, charging and lawful interception. Any protocol that leaks a permanent identifier is treated as a privacy defect, which is why 5G introduced SUCI concealment on the air interface.

To place Grey Route SMS in the wider telecom-security picture, review AAA, Any-Time Interrogation (ATI), Artificial Traffic Inflation, Behavioral Signaling Detection, BTS Impersonation (Fake BTS) and CAP — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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