July 2026

Published 2026-07-01

SEPP PRINS deployments stall; new IRSF vector via A2P

July's watch-list: half of announced 5G SA roaming pairs still ship TLS-only on N32-f, a new IRSF vector exploits A2P termination charging asymmetries, and the first ML-KEM migration profiles land in operator IMS testbeds.

SEPP N32-f: TLS-only remains the norm

5G

Field data across mid-2026 shows that of announced 5G SA roaming corridors, roughly half still run TLS-only on N32-f without PRINS/JWE. Sensitive IEs (SUPI, keys) remain visible to IPX intermediaries in those flows.

A2P termination-fee arbitrage revives IRSF

Fraud

Regulators in several EU markets have flagged a pattern of enterprise SMS aggregators originating apparently-legitimate A2P traffic to high-cost destinations, splitting revenue with grey-route operators. Traditional voice-IRSF detection misses the pattern.

ML-KEM lands in IMS testbeds

5G

Two tier-1 operators disclosed early integration of ML-KEM (Kyber) hybrid key exchange in IMS-AKA testbeds. Interoperability with legacy IMS clients remains the blocker.

GSMA FS.20 update: new GTP-U TEID validation category

Signaling

The next FS.20 revision adds a category for stateful TEID validation, closing a class of TEID hijack attacks that stateless GTP firewalls historically missed.