As deepfakes become more widespread, phishing attacks on companies have become more complex and harder to identify.

Last week, at the world's largest advertising agency, London-based communications and advertising firm WPP, hackers attempted to extort money from employees using the voice and likeness of the company's CEO.

Hackers used WPP CEO Mark Read's public photo to connect to a fake WhatsApp account to schedule a Microsoft Teams video call with company executives.

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In the call, the bad actors used voice-cloning technology and YouTube footage to make it seem like Read was really there at the meeting with the employees.

“The pretext was that the targeted individual was being asked to set up a new business with the ultimate goal of extracting personal data and money,” Read wrote in an email to colleagues first seen by Guardian. “Fortunately the attackers were not successful.”

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WPP works with major international companies including Dell, Wendy's, Uber, Johnson & Johnson and Victoria's Secret.

Read warned employees against “red flags” that could indicate they are being scammed, including asking employees for personal information such as passport numbers or anything related to money transfers or payments that are required to be kept “secret “.

“We have seen increasing sophistication in cyber attacks against our colleagues, and those targeting senior leaders in particular,” Read told employees. “Just because the account has my picture doesn't mean it's me.”

Ironically, the company announced last year that it would be teaming up with chipmaker Nvidia to create AI-generated ads.

“Generative AI is changing the world of marketing at breakneck speed. This new technology will transform the way brands create content for commercial use,” said Read. in a statement in that time.

WPP currently has one estimated market capitalization of 11.43 billion dollars.