The Globe and Mail reports in its Saturday, Oct. 31, edition that a week ago, Canada's top law firms received urgent calls from their IT departments about a software update or expired passwords. The Globe's triple-bylined item led by Tim Kiladze reports that the calls seemed legitimate -- often made through Microsoft Teams or from the IT department's number. In reality, they were from hackers targeting Canadian lawyers. The tactic is called vishing, short for voice phishing -- and it worked. At least four companies were broken into: McCarthy Tetrault LLP, Davies Ward Phillips & Vineberg LLP, Bennett Jones LLP and Borden Ladner Gervais LLP. The damage is still being assessed, but the fallout is significant. Law firms, as trusted advisers, store sensitive files on their servers, including non-public corporate information and clients' tax, financial or health records. Because so much sensitive information is potentially exposed -- at McCarthy Tétrault, 31,000 files were stolen -- some clients are extremely concerned, but so far remain in the dark. Lawyers at the hacked firms have been told which clients were affected, but specific details are often still coming. There's also a fear of more breaches to come.