Blink in Google Chrome prior to 56.0.2924.76 for Linux, Windows and Mac, and 56.0.2924.87 for Android, failed to prevent certain UI elements from being displayed by non-visible pages, which allowed a remote attacker to show certain UI elements on a page they don't control via a crafted HTML page.
https://security.gentoo.org/glsa/201701-66
https://chromereleases.googleblog.com/2017/01/stable-channel-update-for-desktop.html
http://www.securitytracker.com/id/1037718
http://www.securityfocus.com/bid/95792