Some websites shut down globally as operators address PHP issue after AI finds critical flaw

Some websites temporarily offline amid PHP security updates
An AI-assisted discovery of vulnerabilities in a widely used programming language led many websites to temporarily go offline
ABCNews
ByLisa Eadicicco, Hanna Ziady, CNNCNNWire logo
Thursday, October 22, 2026 11:29AM

Government and company websites around the world briefly went dark and suspended some services, as operators scrambled to patch their systems after artificial intelligence helped find critical vulnerabilities in a widely used programming language.

The discovery comes as advancements in AI have raised concerns from Washington to Silicon Valley about how the technology could supercharge cyberattacks.

RELATED: Urgent security fix issued for code vital to estimated 70% of all websites

The US National Security Agency and Europe's cybersecurity agency on Wednesday advised companies to take immediate action to address two critical flaws in PHP, a programming language that powers 70% of all websites in the world, including WordPress and Drupal, an open-source content management system.

The PHP Foundation, the organization behind the coding language, has released a patch for the bugs, which have been hidden in their software for years,and is urging website operators to update their systems immediately.

Popular Irish news website The Journal was temporarily offline Thursday morning while it bolstered its "defences," it said in a notice. The Journal is Ireland's second most-used online news source, behind only RTÉ, the national broadcaster, according to the Reuters Institute.

The flaws in PHP - which originally stood for Personal Home Page - were uncovered by teams at OpenAI, Google-owned cybersecurity company Wiz, and another cybersecurity company, Calif. The bugs, collectively called PHP2Shell, could allow attackers to hack into websites and read memory that could contain sensitive information, like passwords.

World leaders weigh in

Even world leaders urged organizations to take action. Dutch Prime Minister Rob Jetten said that his cabinet was "closely monitoring the situation surrounding the vulnerabilities in PHP."

Japan's Prime Minister Sanae Takaichi said companies should consider suspending services if necessary in order to reduce their exposure. "Please check if your publicly available websites use PHP, and prepare to apply the fix patch that will be released tonight... as soon as possible," she posted on X Wednesday.

Japanese airline ANA, railway operator JR West and the country's largest bank, MUFG, were among companies that reported some webpages and services temporarily suspended.

In Europe, government websites in France, Denmark, Finland and the Netherlands, including the Dutch cyber security agency, were temporarily taken offline while security fixes were implemented.

The Wikimedia Foundation, the non-profit that operates Wikipedia, told CNN Thursday that it was "in the process of addressing security vulnerabilities in PHP," and that a number of its systems had been taken down as a "precautionary measure."

'AI inflection point'

AI played a crucial role in finding and fixing vulnerabilities "that had remained hidden in the PHP codebase for more than a decade," according to Wiz, which said the episode marks an "AI inflection point."

"What AI changed was the ability to understand the weaknesses and turn them into a working exploit," Wiz researchers wrote in a blog post Wednesday. "With frontier AI models and the right tools, a single researcher completed in a week what previously would have taken a world-class team months of work," they added.

The bugs were discovered in late August but were disclosed to the public only on Wednesday, after PHP had come up with a fix.

The flaws could allow attackers to remotely execute code, disrupt services and expose customer data, according to web infrastructure providerCloudflare, which has been working with the PHP Foundation,Calif,OpenAI and Wiz to address the issue.

Researchers at Wiz used Google's Gemini 4 Argon, Wiz Atlas and OpenAI's GPT-5.6 Sol during the research process.

Heartbleed similarities

Wiz researchers say the issue is on par with the Heartbleed bug from 2014, which impacted an encryption technology estimated to be used by two-thirds of the Web. Heartbleed allowed cybercriminals to access data that should have been protected.

Like Heartbleed, the researchers at Wiz say PHP2Shell could similarly serve as a turning point in cybersecurity. While the vulnerabilities existed for years, AI made it practical to deploy them.

"The underlying flaws had been present for decades, but demonstrating their exploitability required an exceptionally complex chain of steps, at the edge of what human researchers could practically achieve," the researchers said.

"Frontier AI models substantially reduced that barrier, turning a longstanding flaw into an exploit."

- John Liu, Anna Cooban and Amy Croffey contributed reporting.

The-CNN-Wire™ & © 2026 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.