Businesses and institutions raced to patch computer systems and braced for slowdowns in system performance, as they—and much of Silicon Valley—reacted to the disclosure this week of two long-hidden vulnerabilities in chips running most of the world’s computers.

The two flaws, dubbed Meltdown and Spectre by researchers that discovered them, provide opportunities for hackers to exploit tricks many modern chips use to speed performance, and steal information in the chips’ memory, like passwords.

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