Fake PDF documents are being used to drive up search engine rankings. They are stuffed with random keywords and links, as well as links to other pages in the campaign. The documents are also showing up on legitimate, but likely compromised, websites. Google has informed SophosLabs about the loophole, but as of yesterday afternoon, the fake PDF documents were still showing up high in results. Users are redirected to a couple of different “get rich quick” websites, a security adviser at Sophos says.”]
Source: https://www.csoonline.com/article/2944677/scammers-bypass-google-filters-with-pdf-cloaking.html