PHP is behind a large part of the internet, but a serious security flaw in the programming language has suddenly brought it into the spotlight. The vulnerability, rated 9.2 out of 10 for severity, prompted website operators and government agencies to rush to secure their systems, with some websites temporarily going offline.

The issue has raised concerns about the security of the technology powering millions of websites and how a flaw that had existed for years went undetected.

What is PHP, and what does it do?

The PHP programming language is an open-source language used to construct and run websites. It works behind the scenes to assist websites in processing data, communicating with databases and displaying information whenever a........

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