A lack of CORS checks in Blink in Google Chrome prior to 66.0.3359.117 allowed a remote attacker to leak limited cross-origin data via a crafted HTML page.
https://www.debian.org/security/2018/dsa-4182
https://security.gentoo.org/glsa/201804-22
https://chromereleases.googleblog.com/2018/04/stable-channel-update-for-desktop.html