UPDATED: Chinese Internet users who leave their computers unprotected are contributing to zombie proliferation, according a report Wednesday by e-mail security vendor CipherTrust.

It almost reads like the movie synopsis to a bad 1950s B-movie slasher, replete with moaning, undead screaming damsels and overdone acting. But the reality of zombied computers is serious.

According to CipherTrust, more than 20 percent of the 157,000 new zombies identified daily come from China, which leads U.S. (16 percent) and South Korea (10 percent) zombie totals. The company tracks these figures using its IronMail e-mail gateway appliances used by customers around the world.

"While the information regarding the number of new zombies per day and the percent originating from China is staggering, it's not necessarily surprising given the number of new Internet users in China," Paul Judge, CipherTrust CTO, said in a statement. "Unprotected computers around the world are vulnerable to compromise within minutes of connecting to the Internet."

China has been experiencing a dramatic increase in the number of Internet users in recent years. According to the China Internet Network Information Center (CNNIC), the number of Internet users has grown from 79.5 million in January 2004 to 94 million in January 2005.

But along with its growth spurt, unprotected Chinese computer systems are increasingly coming under attack from virus writers. A Chinese Ministry of Public Security report in September 2004 found nearly 88 percent of the computers in the country were infected with a virus that year, according to a note from anti-virus firm Sophos.

What spammers want, however, are broadband computers. In many cases, zombied machines are used as a proxy server by operators to launch anonymous spam campaigns. Broadband connections, almost always on and connected, serve nearly as well as a dedicated server. And when the authorities try to trace spam messages back to the source, they usually end up at some unsuspecting PC user's computer, not the spammer.

China's broadband growth has more than doubled in recent times. The CNNIC reported 17.4 million high-speed users in January 2004, a number that grew to 42.8 million by this January.

In related news, CipherTrust officials announced that almost 57 percent of all spam originates in the United States, down from nearly 86 percent in June and July. The U.S. still holds the top spot as the worst spamming country in the world; South Korea landed the second seed at 15.6 percent and China took third with 5.38 percent.

It's no coincidence the U.S., South Korea and China figure prominently in both the number of zombied systems and spam originators, according to Dmitri Alperovitch, a CipherTrust research engineer.

"The problem is there isn't a real serious initiative in any of these countries about protecting the home user, and security is always about the weakest link," he said. "We can do our best to protect enterprises and national critical infrastructure and all those critical systems by following best security practices, keeping a watchful eye over the networks and so on. But if you have these hundreds of thousands of zombies out there, they create a problem for the rest of us."