Blink in Google Chrome prior to 54.0.2840.59 for Windows, Mac, and Linux; 54.0.2840.85 for Android permitted execution of v8 microtasks while the DOM was in an inconsistent state, which allowed a remote attacker to inject arbitrary scripts or HTML (UXSS) via crafted HTML pages.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.