WASHINGTON : Security threats are rising for users of Apple Computer's line of Mac computers, even though risks remain lower than for those using Microsoft Windows systems, a computer security center said Monday.

The SANS Institute, a Washington-based computer research center, said in its updated list of "Top 20 Internet Security Vulnerabilities" that hackers and virus writers are increasingly targeting the Apple operating system.

In its update, SANS cited "rapid growth in critical vulnerabilities" being discovered in the Mac operating system.

The Apple software "still remains safer than Windows, but its reputation for offering a bullet-proof alternative to Windows is in tatters," the report said.

"The reason it is such a problem from a security perspective is that users feel invincible" with Apple computers, said Ed Skoudis, a SANS security analyst who briefed journalists on the latest threats.

Skoudis said many hackers use Apple computers because of the "cleanness of the interchange," and as a result are increasing their search for flaws in the operating software.

Apple's decision to switch to Intel processors may also contribute to the trend because "the bad the guys know the assembly language for the Intel chips."

SANS experts said hackers are finding ways to attack alternatives to Windows including the open-source Mozilla Firefox browser, which is gaining in market share against Internet Explorer.

But they indicated that threats remain high for many PC users who fail to use updated security protection.

"I think it's almost time to rename the Internet Explorer to 'Internet exploiter' because the chances of being exploited (by hackers and viruses) are much higher," said Rohit Dhamankar, a security research and editor of the Top 20 list.

Skoudis noted that some Windows alternatives may appear safer but only they have fewer users and are thus a less attractive target.

"We have just as many vulnerabilities in Mac OS X or in Firefox as with Internet Explorer and Windows, but the bad guys really focus on market share and where the money is."

"So you're probably safer (using these alternatives) but not more secure," Skoudis added. "You're not impervious, don't think you have some shield of invincibility because you're not using Windows."

Skoudis said experts are concerned about the growing threats of "malware," such as viruses and spyware, aimed at financial gain, such as stealing passwords or account information.

This is a shift from the viruses that were strictly nuisances, with profit being the main motive.

"You've seen the rise of a malicious code industry," he said, adding that "the industry has its own research and development arm." - AFP /dt

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