MultiSet

The MultiSet application is classified as a Potentially Unwanted Program (PUP). It relies on questionable distribution tactics (bundling, fake installers, fake updates, etc.) to install itself unnoticed on users' Mac systems. The goal is to then monetize its presence on the system via numerous intrusive methods. In the case of MultiSet, those include acting as adware and a browser hijacker. Other intrusive PUPs are AdvancedServices, DataFile and OperationBeta.

Adware applications are tasked with generating endless intrusive advertisements. The delivered advertising materials may appear as pop-ups, in-text links, banners and more. They may even be added to unrelated pages. Users should not engage with advertisements delivered by such dubious sources or risk being redirected to suspicious or outright unsafe destinations - hoax websites, domains spreading more PUPs, phishing pages, etc.

As a browser hijacker, MultiSet also will attempt to take control over the installed Web browsers. Apps of this type will mostly target the homepage, new page tab, and the default search engine settings, modifying all three to open a sponsored page. Typically, browser hijackers drive artificial traffic towards a fake search engine that would otherwise be completely ignored by the users. Fake engines do not produce results, as they lack the necessary functionality and instead redirect the initiated searches. Users may be shown results from a legitimate engine (Yahoo, Bing, Google) or see their searches taken to a dubious one. In this case, the displayed results may be fairly inaccurate or include numerous sponsored advertisements.

Another serious red flag exhibited by PUPs is their ability to spy on the user's browsing activities. Various data may be tracked and then transmitted to a remote server. The information of interest may include each visited website, clicked links, and initiated search, as well as the device's IP address, geolocation, browser type, ISP and more.