You have to feel sorry for people who shop at TK Maxx, and not just because they seem to have a penchant for outsized American football jerseys with huge cartoon animals emblazoned on the front. This month those shoppers have a lot more to worry about.

TK Maxx has fallen victim to one of the largest credit card heists seen in the UK since I set up that “strictly confidential” Verbal Hiagra premium call line advice centre. Incredibly, the pile-it-high-let-the-shoppers-throw-it-all-over-the-floor clothes retailer has allowed 46 million credit card details to slip through its fingers.

According to TK Maxx, anyone who purchased items from its stores either in the UK or the US between January 2003 and June 2004 is at risk from credit card fraud – and already many have reported that they have felt the long, sticky fingers of the criminally inclined.

The company also admitted in an interview with The Times that it could not rule out other such incidents. “There is a lot more we do not know, and may never know,” a spokesman said.

He added that he couldn’t even say which customers had had their data stolen, which is just about the worst thing a spokesman could be forced to admit. Especially when it seems that there are plenty of systems available that reduce the risk of such incidents.

Now it may be because I am in the privileged position of working for the UK’s leading IT weekly, but for years now hardly an hour has gone by without someone phoning me about some security product or service that would make this sort of thing as likely to happen as the lovely Martine McCutcheon returning one of my phone calls. So how a firm as large as TK Maxx allowed its systems to be as baggy as the jeans it sells for £19.99 is beyond me.

Imagine the damage it has done to its brand. Two weeks ago I was as likely to mention the shop in my column as I am to discuss the ins and outs of my love life with my parents. Now, however, I intend to go on and on and on about it for months.

Shoppers are constantly told to be more careful with their payment details, but as soon as they visit a web site or high-street store, they are surrendering this control. Many shoppers do this freely, many others with a lot of trepidation.

However it is given, trust in a site or a payment system cannot be taken for granted. It has to be earned, and that has just been made a whole lot harder thanks to TK Maxx.