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Security firm Symantec calculated the figure to quantify the scale of fraud it found during a year-long look at the net's underground economy.

Credit card numbers were the most popular item on sale and made up 31% of all the goods on offer.

Coming in second were bank details which made up 20% of the items being offered on criminal chat channels.

The $5.3bn figure was reached by multiplying the average amount of fraud perpetrated on a stolen card, $350 (£234), by the many millions Symantec observed being offered for sale.

Similarly, the report said, if hi-tech thieves plundered all the bank accounts offered for sale they could net up to $1.7bn.

Closed accounts

Symantec said it was likely that many of the cards offered for sale were invalid or cancelled and bank accounts closed but it added: "These figures are indicative of the value of the underground economy and the potential worth of the market.