Amazon's sale starts tomorrow. So does the fake version of it.

Prime Big Deal Days starts at one minute past midnight Pacific time on Tuesday and runs for 48 hours, in 22 countries including the UK, Ireland, France, Germany, Italy, Spain, Portugal and Poland. The deals are real. A good number of the emails about them will not be.

Check Point watched the domain registrations climb. In July there were 905 new web addresses containing Amazon or Prime. By September there were 1,284, a rise of 42 percent, and the company's own classifier flagged one in sixteen of the September batch as malicious or suspicious. The names are built to be glanced at rather than read: amazonprime-support, primevideoamazon, videoamazonprime, amazonprimewindows. Researchers also found two clusters of related sites, eleven in one and five in the other, nearly all of them malicious, set up to look like storefronts and checkout pages.

The emails follow the usual two scripts, a gift card you have apparently won and an account that has apparently been locked, and they are better written than they used to be because writing them well no longer takes any skill. What has not changed is the shape of the trick: every one of them needs you to click a link and sign in on the page it opens.

So do not. If an email or text says there is a problem with your Amazon order, close it and open the Amazon app, or type the address in yourself. A genuine order problem will be sitting there in Your Orders. One that only exists in the email never was one. And if you do shop this week, pay by credit card rather than a bank transfer or a payment app, because the card is the one that can claw the money back. On the PC side, Tendvane's privacy and accounts check will tell you which of your sign-ins still have no second step on them.