A massive SMS spamming operation kicked out tens of millions of text messages, pestering unsuspecting recipients with links to fake sites flogging loans and free money. The operation was simple but smart. The system processed vast batches of phone numbers and curated custom messages on the fly with links to the fake sites. These fake sites urged spam victims to sign up with their name, email address and phone number and promised “free money… for real.” (It wasn’t.) Sometimes confused victims would message the spam number back. If the system spotted certain keywords, like “report” or “FCC,” their number would be added to a “stop list” so they wouldn’t be bothered again.