Microsoft Corp is rushing to fix a bug in its widely used Internet Explorer Web browser after a computer security firm disclosed the flaw over the weekend, saying hackers have already exploited it in attacks on some U.S. companies.

PCs running Windows XP will not get any updates fixing that bug when they are released, however, because Microsoft stopped supporting the 13-year-old operating system this month. Security firms estimate 15 percent to 25 percent of the world's PCs still run Windows XP.

Cybersecurity software maker FireEye Inc. said a sophisticated group of hackers has been exploiting the bug in a campaign dubbed "Operation Clandestine Fox." FireEye declined to name specific victims or identify the group of hackers, saying an investigation is still active.

Microsoft said the vulnerability could let a hacker take complete control of an affected system.

-- Reuters

From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook. Credit: Newsday/Howard Schnapp, Kendall Rodriguez, Drew Singh; Anthony Florio, Randee Daddona, Morgan Campbell, Debbie Egan-Chin

Get ready for sun and fun with NewsdayTV's summer FunBook special! From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook.

From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook. Credit: Newsday/Howard Schnapp, Kendall Rodriguez, Drew Singh; Anthony Florio, Randee Daddona, Morgan Campbell, Debbie Egan-Chin

Get ready for sun and fun with NewsdayTV's summer FunBook special! From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook.

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