If you think you are using Google Chrome , check again , it could be "eFast Malware" in disguise

Nice , simple but an very effective trick.



From the article:

According to security bloggers at Malwarebytes, the malware installs itself as the default internet browser and the default program for various popular file types, including .html, .jpg, .gif and .pdf, as well as a number of web links such as http, https and irc.


eFast is able to mirror the aesthetics of Chrome as it uses the same source code, available across the open-source project Chromium.

eFast places ads across existing web pages, linking to third-party e-commerce sites or other malicious platforms.


For More info:
https://thestack.com/security/2015/10/20/efast-malware-hijacks-browser-with-chrome-clone/