Global firms and governments rushed to patch critical flaws in the PHP programming language following the disclosure of vulnerabilities uncovered using artificial intelligence. Cloudflare reported millions of hacking attempts after the vulnerabilities were disclosed.
On 21 October, governments in Europe and elsewhere took websites offline as a precaution. PHP developers released fixes for the flaws on 21 October.
Microsoft CEO Satya Nadella said, "I've not seen anything like this in a long, long time." Madeline Lawrence said, "Companies are racing to update against attackers who can use AI to exploit them. That's the whole race."
Several Asian governments ordered cybersecurity inspections related to the PHP vulnerabilities on 22 October. South Korea raised its private-sector cybersecurity alert level and activated emergency response measures.
On 22 October, Nomura, Mitsubishi UFJ Financial Group, ANA and East Japan Railway temporarily suspended some internet services. Brewer Asahi Group Holdings temporarily suspended certain websites and systems, while Tokio Marine Holdings suspended its group website.
Japan's Ministry of Finance and Meteorological Agency partially suspended online services, and Japan's National Tax Agency temporarily took down its service. Japan recorded more cyber incidents in the first 9 months of 2026 than in all of 2025.
Orange temporarily suspended access to certain PHP-based websites and applications. Tencent Cloud urged customers to install updated PHP versions.
Valtori continued installing PHP security patches overnight and was gradually lifting precautionary service blocks. Valtori stated outages were not caused by exploitation of vulnerabilities or by a cyber breach.
Valtori Director General Hannu Naumanen said, "Restoring services can take days or even weeks, as in addition to updates, the systems need to be carefully tested." Felix Kuhlenkamp said, "They may run a website using PHP but don't really keep a close eye on it."
Kuhlenkamp added, "If a website is based on an old version of PHP for which there is no security update, the entire system must be updated."
