Port-Out Fraud

In telecom networks, Port-Out Fraud is the unauthorized transfer of a victim's MSISDN from their current operator to one controlled by the attacker, often using social engineering against customer support. Once ported, the attacker receives the victim's calls and SMS, enabling account takeover of bank, email, and crypto accounts.

Categories: Radio Access NetworkIdentity and SubscriberSecurity Controls

Port-Out Fraud in context

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

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

To place Port-Out Fraud in the wider telecom-security picture, review SIM Swap, eSIM Profile Theft, IMSI Catcher (Cell Site Simulator), MNP, WCDMA and OTA.

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