An issue was discovered in certain Apple products. Safari before 11.1 is affected. The issue involves the "WebKit" component. A Safari cross-site scripting (XSS) vulnerability allows remote attackers to inject arbitrary web script or HTML via a crafted URL.
https://usn.ubuntu.com/3635-1/
https://support.apple.com/HT208695
https://security.gentoo.org/glsa/201808-04