Russian SIMs. Encrypted SIMs. White SIMs.
Beyond spoofing phone numbers, some SIMs let a caller manipulate their voice in real-time, adding a baritone or shrill cloak to their phone calls that is often unintentionally funny. Other cards have the more worthwhile benefit of being worldwide, unlimited data SIMs that criminals source anonymously from suppliers without having to give up identifying information and by paying in Bitcoin.
The SIM cards themselves aren't inherently illegal, but criminals certainly make a noticeable chunk of the companies' customer bases. The NCA told Motherboard it has seized so-called Russian SIMs from suspects during investigations. more
