日々更新mobilerA8（Yahoo!ニュースを毎日ウォッチ）

日本ではあまり普及していないデビットカード。
クレジットカードではなく、直接銀行から預金を購入店へ振り込むというようなもの。
アメリカの銀行はハッカー対策として、この額に上限を設けるということだ。

PCI データセキュリティ基準 完全対策 新品価格 ￥2,940から (2013/12/27 08:22時点)

ＢＢＣより。
US banks move to limit Target debit card breach damage
http://www.bbc.co.uk/news/technology-25493536Debit card limits are being cut for two million Americans following a hack attack on US retailer Target.

Details of more than 40 million cards were stolen by thieves who compromised card swipe systems at Target's tills.

Bank JP Morgan Chase said it was reducing limits on all cards used at Target while thieves had been scooping up data.

Security researchers said the stolen card numbers had been seen on underground markets.

Card losses

The thieves managed to grab the key details for so many cards by getting malware onto the computer systems at the checkout desks in almost 1,800 Target stores in the US. It is still not clear how the thieves managed to get their malware onto the systems.

The thieves had access to card data read at the tills for almost three weeks, said Target in a statement released after it realised it had been under attack.

JP Morgan Chase said it had lowered daily spending limits to $300 (£183) and daily cash withdrawal limits to $100 on potentially vulnerable cards as a "precaution".

Reuters reported that other US banks are also believed to be putting stringent precautions in place that would help to spot if cards were being used fraudulently. In addition, Target said it would offer free credit monitoring for customers affected by fraud.

On 20 December, security researcher Brian Krebs said there was evidence that card numbers stolen in the Target attack had shown up on underground markets where such details are traded.