http://torzcd47rw4qh36g4yqxvv2tmifgmu6jjalkyqz4e4lzzwtfdfc7qaqd.onion/apple-fixes-zero-day-spyware-implant-bug-patch-now-mobile-hacker-for-hire/index.html
(Note that this doesn’t immunise you from security problems, given that Gecko and Blink may bring along their own additional bugs, and given that plenty of Mac software components use WebKit anyway, whether you steer clear of Safari or not.) But on iPhones and iPads, all browsers, regardless of vendor, are required to use the operating system’s own WebKit substrate, so all of them, including Safari, are theoretically at risk when a WebKit bug shows up.