DAVID GREENE, HOST:
NPR's business news begins with some cyber insecurity.
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GREENE: Microsoft is warning that a flaw in its Internet Explorer Web browser leaves the program vulnerable to hackers. It's apparently been exploited to target financial and defense companies. The biggest risk is to users still running the Windows XP operating system, which Microsoft stopped supporting with updates and security patches a few weeks ago. Transcript provided by NPR, Copyright NPR.