XSS Auditor in Google Chrome prior to 64.0.3282.119, did not ensure the reporting URL was in the same origin as the page it was on, which allowed a remote attacker to obtain referrer details via a crafted HTML page.
https://www.debian.org/security/2018/dsa-4103
https://chromereleases.googleblog.com/2018/01/stable-channel-update-for-desktop_24.html
https://access.redhat.com/errata/RHSA-2018:0265