How a 4-Year iPhone Hack Exposed a Major Security Flaw 

A security flaw in Apple's iOS and macOS devices allowed hackers to take full control of them by sending a malicious PDF file.

The flaw affected the kernel and WebKit, the core components of the operating system and the web browser.

 Apple said it was aware of reports that the flaw was actively exploited by hackers, but did not provide details.

Security experts advised users to update their devices as soon as possible to protect themselves from the vulnerability.

The flaw was similar to another one that was exploited by NSO Group, an Israeli spyware company, to target iPhones with its Pegasus malware.