Experts say Microsoft business accounts might still be vulnerable following cyberattack

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PHILADELPHIA (KYW Newsradio) — Experts said a global cyberattack breaching thousands of Microsoft business accounts last week was sophisticated and should be taken seriously.

Microsoft said the attack on Tuesday started with a Chinese government-backed hacking group affecting 60,000 businesses using its email service.

"This one is really more serious," said Drexel University Chief Information Security Officer Dr. Pablo Molina. "Basically, it attacks one of the most-used applications of internet traffic which is electronic mail."

So far, many of the businesses affected appear to be small or medium-sized. Molina said the attack was actually detected back in January and grew more aggressive last week.

"It came to prominence last Tuesday when Microsoft released patches to all of its Exchange products used in data centers and organizations worldwide," Molina explained.

With that, he said they gained access through a backdoor and siphoned out and copied emails, gaining access to other parts of the networks of these organizations.

Although Microsoft has worked to end the hack, Molina said, "If people do not patch their systems and then investigate whether or not their systems have that backdoor, they could be vulnerable to the bad guys."