US cybersecurity software giant CrowdStrike closed down 11.1% at $12.767 billion, causing the largest IT system failure in history. Starting from early Friday morning local time in the United States, due to serious errors in software updates pushed by CrowdStrike, Windows computers worldwide using their software have collectively fallen into a "blue screen ocean". Many airports, shopping malls, hotels, as well as offices, factories, and stock exchanges have been paralyzed as a result. The CrowdStrike security software bug caused the collapse of Microsoft's Windows system, leading to what the media called the "largest IT system failure in global history".