The browser hijacker Youndoo, discovered earlier this year, is now adding an extra Google Chrome profile to victims' machines, copying settings from users' current profiles so they don't necessarily notice the difference when their settings are switched, according to researchers at Malwarebytes.

Infected users who look at their Chrome settings will notice a gray icon with account name “user0” instead of their own name and image. Users' extensions and histories are copied to this new account, but the start page is changed to, which becomes the default search engine, Malwarebytes reported Tuesday in a blog post. Manually changing the settings back to the previous configuration won't undo the changes either; a system reboot is also required – and even then, Malwarebytes advised killing the program altogether, which is typically found bundled in free software downloads.