Bad casting in bitmap manipulation in Blink in Google Chrome prior to 55.0.2883.75 for Mac, Windows and Linux, and 55.0.2883.84 for Android allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
https://security.gentoo.org/glsa/201612-11
https://chromereleases.googleblog.com/2016/12/stable-channel-update-for-desktop.html