VERY IMPORTANT

From 2019-20, Palo Alto Unit 42 noticed a dramatic 1,160% increase in malicious PDF files – from 411,800 malicious files to 5,224,056. PDF files are an enticing phishing vector as they are cross-platform and allow attackers to engage with users, making their schemes more believable as opposed to a text-based email with just a plain link. To lure users into clicking on embedded links and buttons in phishing PDF files, Palo Alto has identified the top five schemes used by attackers in 2020 to carry out phishing attacks, which Palo Alto has grouped as Fake Captcha, Coupon, Play Button, File Sharing and E-commerce.