The entire internet is under threat from the rackets and scams of the “digital mafia” unless the global anti-virus industry dramatically changes the way it protects our computers.

The problem is so dire, says Eva Chen, chief executive of Trend Micro, the software giant, and a 20-year veteran of the antivirus battle, that hackers are conducting online auctions for people’s personal details. A name and a matching social security number fetches $24 (£12.20), while a credit card number with the owner’s name, expiry date and security PIN can be had for just $96.

Ms Chen, who recently became Japan’s most powerful businesswoman, says that the online assault from viruses has expanded far beyond the industry’s expectations. From 1990, it took 15 years to assemble a worldwide library of 100,000 viruses, and, she warns, “that number has tripled since 2005”.

In an exclusive interview with The Times, Ms Chen describes an $8 billion (£4.05 billion) online black economy centred on credit-card theft, corporate blackmail and insider share dealing. She adds that the advent of so called Web 2.0 — the new phase where internet users share and produce vast quantities of online content — has exacerbated online criminality.

The chief problem, she says, is that while hackers used to boast loudly about their ability to “bring down the internet”, or lay waste the computer systems of a corporation, those same individuals have become “silent killers” with a greater taste for profit than for notoriety. “Our business changed overnight when hackers first realised they could make money,” Ms Chen says.

The hackers’ methods have also shifted. Rather than producing a single virus, the new strategy is to build a command centre and control millions of “zombie” PCs without their owners’ knowledge. By commandeering that volume of computers, the hackers can mount mass frauds and blackmail businesses with the threat of overloading their systems.

The response by the antivirus software makers is to mount a different type of defence: devoting resources to finding the hackers’ command centres and severing their links with their zombie armies.

The blackmail money demanded by the hackers, Ms Chen notes, is always slightly below the cost of buying a full corporate defence package from Trend Micro.

“We are fighting a battle that will grow as more money floats around the digital world. We have to make a sea change in the way we deal with antivirus issues or the internet world will lose to the hackers and our mission has failed,” she says.

Big shot: Eva Chen

As even she acknowledges, there are two rather glaring oddities in crowning Eva Chen Japan’s most powerful businesswoman: first, she is Taiwanese and, second, she lives in Pasadena.

But the 48-year old computer engineer and now chief executive of Japan’s largest antivirus software firm, Trend Micro, has other concerns. “If I really am Japan’s most powerful businesswoman, then it’s a sad state for us,” she says, adding that Japan’s future must surely lie in tapping the still underexploited talents of half its population.

Ms Chen’s new status highlights the difficulties women face in advancing within the traditional structures of Japan Inc. Her crown is only recently won. The previous title-holder, Tomoyo Nonaka, was a former television newsreader parachuted in as the chairman of Sanyo to become the face of its turnaround. Her inexperience running a vast conglomerate was swiftly exposed and her resignation came prematurely last month.

Ms Chen, meanwhile, is a US-educated software engineer and one of the three founders of Trend Micro. Though the company has its HQ in Tokyo, her business experience was earned through its global ambitions and lack of Japanese structure.

She recalls with visible distaste her early experiences in Japan as a senior female executive. “I went into one meeting with a junior Japanese colleague — a man — who begged me not to give the people we were meeting my business card showing that I was his boss,” she says. “He told me he had no way of telling them that his boss was a woman. It was crazy. I had to make out I was a sort of secretary, and pretended to be writing notes, when in fact I was writing questions for my colleague to ask.”

But she says things are changing in Japan, especially in the IT industry where the relative youth of those involved means that some of Japan’s more antiquated attitudes do not exist. Her Japanese colleagues, she notes with interest, are now prepared to talk about the once taboo subject of their families.

But Ms Chen is quick to downplay some issues. “Being nonJapanese, being always on the move, being a woman is not difficult. Running a global company is. My staff are not in the same country and come from many cultures. We have 18 languages in the company and seven in the boardroom alone. The only common language is broken English.”

She is also matter-of-fact about the risks of the industry she has chosen, brushing aside the various threats that are made against antivirus gurus like her. “I don’t live my life in fear of the hackers. My biggest fear is that people think that I’m not doing a good job of beating them,” she says.

In terms of legacy she is, officially at least, an equal-opportunities chief executive. When pushed, she admits a certain bias: “I came into this job searching for my successor. Will that person be a woman? I’m silently hoping so.”

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