SIM box (SIM farm)
A SIM box is a rack of SIM cards that sends texts in bulk while constantly rotating numbers — the basic tool of industrial smishing campaigns.
In brief
A SIM box is a rack of SIM cards that sends texts in bulk while constantly rotating numbers — the basic tool of industrial smishing campaigns.
Going deeper
The rack holds tens to thousands of SIM cards and automates sending. Rotating the sender numbers spreads the volume thin and frustrates carrier spam filters, which are best at spotting a single number that talks too much.
These installations feed smishing campaigns: delivery, fine or bank-account messages sent in waves. A text received this way can be reported to 33700 in France, which helps carriers trace and cut off the source.
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