Phone numbers
SMS pumping
SMS pumping is fraud in which attackers trigger large numbers of text messages, such as one-time passcodes, to phone numbers they profit from.
How it works
The fraud works because some carriers share the fee for each delivered message with the number's owner. The attacker submits your sign-up or login form with numbers in those ranges, and you pay for every message sent.
Common defences are rate limits per number and per client, checking the number type and country before sending, and watching for bursts of requests to unusual ranges.
Related LookValid products
| Product | Credits | Docs |
|---|---|---|
| Phone Numbering-Plan Validation | 1 credit per valid number | API docs |
| Phone Spam Check | 1 credit per number with complaints on record | API docs |
| Fraud Detection | 1 credit per request (up to three checks in one call) | Product page |
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