Wholesale glossary
Wangiri (one ring and cut) is callback fraud: a machine calls a subscriber from a premium-rate number, hangs up after one ring, and profits when the subscriber calls back. Also known as IRSF, International Revenue Share Fraud, it is one of the top revenue losses carriers report, and it succeeds because the victim places the call voluntarily.
Why it matters
Every callback is billed at premium international rates, and the fraudster shares revenue with the premium rate service provider. A single campaign can hit thousands of subscribers overnight, which is why regulators and the GLF run dedicated wangiri awareness programmes.
What practitioners watch
Watch for short-duration incoming spikes from number ranges with premium-rate associations, clusters of one-ring calls to many B-numbers from few A-numbers, and callback patterns following minutes after the ring. Blocklists like the RAG wangiri list help; per-corridor baselines catch the rest.
Related: Fraud Prevention · SIM Box Fraud · A-Number