Researchers from ThreatTrack Security Labs have found that searching for "Google Chrome Browser" in Yahooo Search Engine displays rogue ads.
Clicking the rogue ad leads users to a website that serves fake google chrome and urges users to install their own download manager "WeDownload Manager".
This is not new that rogue websites serving a free software to download. They are usually modified to install adware. However, in this case, the fake browser served in this website is notorious "Sirefef/ZeroAccess" malware.
Once the fake browser is executed, it delete itself and install Adobe Flash Player while it infect the victim's system in the background.
The malware disables the windows security and prevent the OS from updating automatically.