Work in finance or accounting Watch out for 'whaling' attacks

That's because so-called "whaling" attacks -- a refined kind of phishing in which hackers use spoofed or similar-sounding domain names to make it look like the emails they send are from your CFO or CEO -- are on the rise, according to security firm Mimecast.

In fact, 55 percent of the 442 IT professionals Mimecast surveyed this month said their organizations have seen an increase in the volume of whaling attacks over the last three months, the firm reported on Wednesday.

Those organizations spanned the U.S., U.K., South Africa and Australia.

Domain-spoofing is the most popular strategy, accounting for 70 percent of such attacks, Mimecast said; the majority pretend to be the CEO, but some 35 percent of organizations had seen whaling emails attributed to the CFO.

“Whaling emails can be more difficult to detect because they don’t contain a hyperlink or malicious attachment, and rely solely on social engineering to trick their targets,” said Orlando Scott-Cowley, a cybersecurity strategist with Mimecast.

Often, sites like Facebook, LinkedIn and Twitter give attackers the details they need to execute whaling attacks, Mimecast said.

So what's an accountant to do Mimecast has a few suggestions.

Educating senior management, key staff and finance teams is one of them; another is conducting tests on your own business through mock whaling attacks to see how vulnerable your staff are.

Inbound email stationery that marks emails originating outside the corporate network can be another useful tool, as can domain name registration alert services, which will alert you when domains are created that closely resemble your company's.

“The barriers to entry for whaling attacks are dangerously low," said Scott-Cowley. "As whaling becomes more successful for cybercriminals, we are likely to see a continued increase in their popularity."