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AI helps find vulnerability affecting up to 70% of websites

Oct 21, 2026, 6:44pm EDT
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A computer displays the unavailable Dutch website
Annegret Hilse/Reuters

France, Denmark, Finland, and the Netherlands took government websites offline Wednesday after web developers used AI to identify a bug affecting up to 70% of the world’s websites.

The exploit is “the most severe AI vulnerability… ever found,” the co-founder of Google’s Wiz cybersecurity team told The Wall Street Journal, adding that humans probably couldn’t have discovered it without AI.

Japan’s prime minister also urged “everyone to take action tonight” to apply the newly-released fixes. But AI will enable hackers to reverse engineer the bug in a “race to exploit” the public fix, a cybersecurity researcher told Reuters, with their next step being the “mass compromise of every vulnerable web server ​on the internet.”

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