Man-in-the-Middle (MITM)

A Man-in-the-Middle attack places the attacker between two communicating parties, intercepting and possibly modifying their traffic while each side believes it is communicating directly with the other. Telecom-specific MITM scenarios include IMSI catchers on the radio interface and SS7 redirection in the core. Mutual authentication and end-to-end encryption are the principal defences.

Categories: Radio Access NetworkCore NetworkSignaling

Man-in-the-Middle (MITM) 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.

The mobile core carries subscriber sessions, mobility and policy. 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.

To place Man-in-the-Middle (MITM) in the wider telecom-security picture, review 5G SA, AMF, Base Station (BS), Capacity Planning, CAPEX and CSCF — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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