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A lone New Zealand hacker has triggered a security scare that had Microsoft software engineers in the United States working through their Thanksgiving holiday weekend to fix a design flaw in Windows software.
Beau Butler - who describes himself as an "ethical hacker" - revealed at the NZ computer security conference Kiwicon this month that the flaw was exposing millions of computers to hijacking by criminals.
Mr Butler said that while testing the flaw, he found more than 160,000 computers in NZ were vulnerable.