WASHINGTON — Someone pretending to be Secretary of State Marco Rubio used AI-generated voice technology and a fake Signal account to contact foreign officials and at least one member of Congress, the latest case of impostors mimicking senior U.S. officials.

A State Department cable dated July 3 said an unknown person left voice and text messages for at least five people, including “three foreign ministers, a U.S. governor and a U.S. member of Congress” after creating a Signal account that pretended to be Rubio’s in mid-June.

“The actor likely aimed to manipulate targeted individuals using AI-generated text and voice messages, with the goal of gaining access to information or accounts,” according to the cable, a copy of which was seen by Bloomberg News.

The campaign fit with a pattern of cases dating to April that saw unknown hackers impersonate senior US officials. In late May, the Wall Street Journal reported that authorities were investigating an effort to impersonate White House Chief of Staff Susie Wiles. The person claiming to be Wiles had contacted senators, governors, top US business executives and others, it said.

The impersonators used AI-generated voice messages and text messages in order to “establish rapport before gaining access to personal accounts,” according to a Federal Bureau of Investigation note from May 15.

Ben Colman, chief executive officer of Reality Defender, a deep-fake detection company which helps platforms flag fraudulent calls, audio and video, said it’s become simple to create the kind of audio deep-fakes that the State Department cable cited.

“It’s easy enough that my 8-year-old or my 80-year-old parents can do it without any technical ability,” Colman said. “Unlike ransomware or a traditional computer virus, anybody with an internet connection and browser for Google search can make an incredibly entertaining or incredibly dangerous deep-fake of absolutely anybody.”

The State Department didn’t immediately respond to a request for comment on Tuesday. The Rubio impersonation was first reported by the Washington Post.

Impersonators may be using Signal because they know it’s a popular messaging app among top government officials. In March, the White House faced an uproar after The Atlantic reported its top editor had been added to a Signal group chat where top officials discussed secret plans to attack Houthi rebels in Yemen.

That chat included Rubio, Wiles, Defense Secretary Pete Hegseth, Vice President JD Vance, then National Security Adviser Mike Waltz and other top officials, and was considered a major security breach.

According to the latest cable, the State Department is also tracking a separate campaign that began in April in which a Russia-linked actor posed as a State Department official to target the Gmail accounts of activists, dissidents and journalists in Europe.

“The actor demonstrated extensive knowledge of the Department’s naming conventions and internal documentation,” the cable said.

It cited past efforts, such as a June 2022 incident where someone created a WhatsApp account purportedly belonging to then-Secretary of State Antony Blinken that sent messages to two South American Leaders. In 2023, it said, a “likely Russian state-sponsored cyber threat actor” impersonated State Department accounts to target organizations working on non-proliferation.

“We’ve seen a huge increase in volume of these type of attacks,” said Brian Long, chief executive of the deep-fake protection firm Adaptive Security. “People don’t understand how quickly the technology has developed and what’s now possible.”

______

(With assistance from Margi Murphy and Patrick Howell O'Neill.)

©2025 Bloomberg L.P. Visit bloomberg.com. Distributed by Tribune Content Agency, LLC.