Hackers Using PDFs to Impersonate Microsoft, DocuSign, and More in Callback Phishing Campaigns

Cybersecurity researchers are calling attention to phishing campaigns that impersonate popular brands and trick targets into calling phone numbers operated by threat actors. "A significant portion of email threats with PDF payloads persuade victims to call adversary-controlled phone numbers, displaying another popular social engineering technique known as Telephone-Oriented Attack Delivery (TOAD