Card Skimming & ATM Skimming

What it is

Card skimming is the unauthorized copying of payment-card information at a machine or reader. An external skimmer captures magnetic-stripe data, while a thin device called a shimmer may be hidden inside a chip reader. Attackers may separately record your PIN. What they can do with the stolen information depends on the card technology and the issuer's controls.

How it works

A reader is placed over or inside a legitimate slot. A concealed camera or false keypad records PIN entry, and the attacker collects the stored data later or remotely. Copying card information does not necessarily duplicate a chip's transaction authentication, but criminals may try online fraud or magnetic-stripe misuse where those channels remain available.

How people get tricked

The ATM still dispenses money and belongs to a familiar bank, so nothing appears wrong during the transaction. Hidden internal devices may leave no visible sign; inspection reduces risk but cannot prove a machine is safe.

Example scenario

You withdraw cash at an outdoor ATM with an unusually bulky card slot. Days later, your issuer flags unfamiliar withdrawals. A camera may have captured the PIN while the added reader copied card data.

Warning signs

• Loose, bulky, or mismatched parts around the card slot or keypad.
• An unexpected card-reading problem or suspicious attachment.
• Withdrawals or purchases you did not authorize.

If it happens to you

Stop using a suspicious machine and notify its operator without removing the hardware yourself. If you suspect exposure, freeze the card and contact the issuer to dispute activity and arrange replacement or a PIN change. Record the location and time of use.