Seeing an email from your firm's managing partner flash up on your phone is something that would give even the most laid-back lawyer pause for thought, let alone if your boss is asking to see you urgently.

But before typing back a quick, slightly panicked response, asking what's wrong and why they are needed, lawyers are now having to confront a different, more sinister possibility: is this email really coming from my boss? Or is it coming from a total stranger?

One managing partner at a U.K. firm says that his lawyers have been targeted by email phishing scammers several times in recent months, part of a wave of phishing attacks to have hit law firms.