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 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.

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 Port-Out Fraud in the wider telecom-security picture, review 2G, Authentication, IMSI Catcher (Cell Site Simulator), OTA, USIM and WCDMA — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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