The Explore worm, which can hide and possibly destroy commonly used files on a user's hard drive, forced many firms -- including Boeing Co., Microsoft Corp., SBC Communications (NYSE:SBC) and Forrester Research Inc. -- to take down servers to prevent wider damage. Starbucks Corp. asked users on the network in its corporate headquarters in Seattle to shut down their PCs while it addressed the problem, a spokesman said. He noted that its stores were unaffected.
Dave Suffia, a spokesman for Boeing, said his company noticed the problem late Thursday morning and warned employees through e-mails and calls about the worm's features.
"We had to shut down our Exchange system to protect the computers and protect further spread," Suffia said.
He said the servers would stay down -- at least overnight -- while Boeing worked with Microsoft (Nasdaq:MSFT) to find a solution.
Microsoft plagued, too
But Microsoft also had its hands full. The software giant took down mail servers that connect to the Internet for two hours starting at 9 a.m. Thursday while technicians attacked the problem.
As a result, employees could not send or receive e-mail messages from outside the company network, a Microsoft spokesman said.
At Forrester Research, several analysts noticed that some of the files they had worked on the day before had been reduced to zero bytes. "We knew we had a virus," said analyst Ted Julian, who covers the security industry for Forrester.
The market research firm took down a few servers to prevent the problem from spreading. Julian said the damage was contained because the company detected the worm early and had backed up its data overnight.
Julian called Explore the latest in a "steady march of attacks," and he predicted they would continue.
"The reality is that these incidents are on the rise, and no one is immune, no matter what technology they have in place," Julian said.
Escalating virus war
Meanwhile, anti-virus companies scrambled.
Carey Nachenberg, chief researcher at the Symantec AntiVirus Research Center said malicious hackers have been inspired by the publicity accorded recent virus attacks such as Melissa, which wreaked havoc on corporate networks in March.
He said Melissa offered a lesson to copycat hackers who saw how easy it was to exploit features of Outlook and Exchange to spread viruses or worms.
Nachenberg said Explore could hit more home users than Melissa because it automatically responds to incoming e-mails, meaning employees may spread it to friends who e-mail them at work.
"It's obviously more malicious than Melissa," Nachenberg said. "This is probably going to hit a wider variety of users."
Scott Johnson, lead systems engineer at network protection software maker Content Technologies, said the fast-spreading Melissa virus taught companies to take preventative measures. That's why more companies took their servers down sooner after this latest outbreak.
"People are a little shell-shocked and are more likely to err on the side of security," Johnson said.
Holes in Microsoft software?
But Johnson also blamed features in Microsoft's software for the spread of the virus. The company's applications contain many features that allow them to work together easily with other software programs. But Johnson said malicious hackers can exploit security loopholes in Microsoft applications.
"The extensibility that Microsoft built into their products is their Achilles' heel," Johnson said. "They haven't necessarily put the security measures into their products to prevent this."
Michael Fitzgerald contributed to this story.
