https://thenextweb.com/security/2019/08/20/ios-12-4-makes-it-possible-to-jailbreak-your-iphone-again/

Apple’s most recent iOS update — 12.4 — has reopened a vulnerability that was previously patched, making  it easy to jailbreak iPhones and iPads.

As reported by Motherboard, hacker Pwn20wnd exploited the flaw to release a public version of the jailbreak on Monday, making it the first time an up-to-date firmware has been unlocked in years.