US senator targeted by deepfake caller posing as Ukrainian diplomat

A deepfake “actor” imitating Ukraine’s recently departed foreign minister targeted the chairman of the Senate’s powerful foreign relations committee in a suspected attempt at election interference, US officials have confirmed.

Ben Cardin, the Democratic senator for Maryland, grew suspicious during a pre-arranged Zoom call on 19 September with a person posing as Dmytro Kuleba, who stepped down as Ukraine’s top diplomat in a government reshuffle this month.

The individual presumed to be Kuleba had contacted Cardin’s office by email requesting a video meeting. The two men had met previously.

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“[W]hen they connected on Zoom, it appeared to be a live audio-video connection that was consistent in appearance and sound to past encounters,” according to a notice issued by the Senate’s security office.

But Cardin – who is himself retiring as a senator at the end of the year – sensed a trap when the individual purporting to be Kuleba started asking “politically charged questions in relation to the upcoming election”, continued the notice, which did not name the senator involved.

Cardin’s identity was confirmed by the website Punchbowl, which first reported the story.

The notice added that the person, whose face and voice were consistent with Kuleba’s, “began acting out of character and firmly pressing for responses to questions like ‘Do you support long range missiles into Russian territory? I need to know your answer.’”

Cardin promptly ended the call and alerted the US state department, which confirmed that the individual was not Kuleba.

The matter is now being investigated by the FBI, which has not commented.

Senate security officials believe the voice and image resembling Kuleba was generated by artificial intelligence. The Senate security office said the impersonation had “technical sophistication and believability”.

While there was no confirmation of who might have been responsible, the concern over Ukrainian missiles points the finger at Russia. Vladimir Putin warned on Wednesday that Russia would consider using nuclear weapons in response to a concerted Ukrainian missile attack on its territory.

In a statement, Cardin confirmed he had been contacted by a “malign actor” who he said “engaged in a deceptive attempt to have a conversation with me by posing as a known individual”.

The statement added: “After immediately becoming clear that the individual I was engaging with was not who they claimed to be, I ended the call and my office took swift action, alerting the relevant authorities.”

A second Senate security notice, from the cybersecurity awareness center, warned “of an active social engineering campaign … that is targeting senators and Senate staff.

“Targets are contacted by threat actors posing as representatives of a foreign dignitary requesting an official video call that is, in reality, malicious,” said the notice. “This technique is used to discredit the victim or gain additional information. Threat actors leverage existing relationships and other known information to appear legitimate.”