The resurgence of eavesdropping skimming

The range of security threats facing financial institutions today is extensive, and is growing and evolving all the time. The explosion of the digital space has opened up many new avenues of attack for criminals, but banks must also be aware of the risks facing traditional channels, such as the ATM.

Ongoing innovation in protective measures makes life more difficult for criminals, but past trends have shown that there will always be a new threat ready to take the place of one that has just been nullified, even in long-established channels.

This can be seen with the recent re-emergence of ATM eavesdropping skimming.

What is eavesdropping skimming?

Eavesdropping skimming is a technique that involves the fascia of the machine being penetrated, giving the criminal access to the card reader.

A skimming device is placed directly onto the card reader, targeting a point where an electrical node carries card data.

This method has previously been identified mainly in the UK, but there have been more recent reports of eavesdropping skimming attacks in the US and Europe. Earlier attacks sought to access the card reader’s electronic control board via a hole behind the ATM card orientation window. More recent incidents have used the same principle, but with slightly different methods.

Attackers cut a hole in the ATM fascia to place an eavesdropping skimmer directly beneath the card reader, then disguise the hole with an overlay panel that matches the color of the machine. Once this device is in place, the perpetrator has the capability to acquire card data as it is read by the ATM.

This technique represents a different approach from traditional bezel-based skimming, which involves a bogus card reader being placed over the ATM’s real exterior card slot. Consequently, the fight against eavesdropping skimming requires unique measures.

Combating eavesdropping skimming

One of the most important things for financial institutions and ATM operators to do to protect their fleet against eavesdropping skimming is to conduct regular inspections. In addition to this particular threat, frequent checks can help to identify anomalies such as cameras installed to record customer PINs.

Proven safeguards against traditional skimming – such as fascia-fitted solutions that use detectors and jammers to prevent criminals from acquiring card data – will be ineffective against eavesdropping skimming.

However, there are dedicated anti-eavesdropping products available, which should be used alongside established protections against fascia skimmers.

Another important consideration for financial institutions and ATM operators is the software they have installed in their machines. Specialist detection software can identify the presence of a fraudulent device within an ATM, enabling the business to take action as quickly as possible.

Skimming is one of many security risks in the self-service ATM channel. Other threats include card trapping, cash trapping, brute-force attacks and compromised software. Banks and independent operators need to ensure they are not only aware of these dangers, but have a clear strategy in place to mitigate and tackle them.


Image credit: iStock/sirastock

Written by Owen Wild

Owen Wild

Owen is responsible for marketing strategies for the NCR Security Solutions within NCR’s Financial Solution Portfolio. Over the past 15 years, Owen has held several sales and marketing positions with leading travel and tech companies.

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