U.S. National Security Advisor Mike Waltz checks his mobile phone while attending a cabinet meeting held by U.S. President Donald Trump at the White House in Washington, D.C., U.S., April 30, 2025. REUTERS/Evelyn Hockstein TPX IMAGES OF THE DAY
WASHINGTON (Reuters) -The communications app used by U.S. President Donald Trump's former national security adviser, Mike Waltz, said Monday that it had suspended services following a reported hack that exposed some of its messages.
The Department of Homeland Security separately said that customs officials had disabled the app on their devices.
Portland, Oregon-based Smarsh, which runs the TeleMessage app, said in an email it was "investigating a potential security incident" and was suspending all its services "out of an abundance of caution."
Smarsh did not immediately respond to a request for more detail about the breach. DHS said in an email the U.S. Customs and Border Protection agency had "immediately disabled TeleMessage as a precautionary measure."
"The investigation into the scope of the breach is ongoing," it said.
A Reuters photograph showed Waltz using TeleMessage, an unofficial version of the popular encrypted messaging app Signal, on his phone during a cabinet meeting on Wednesday.
Waltz was ousted the following day, a move that capped weeks of controversy over his creation of a Signal group to share real-time updates on U.S. military action in Yemen.
That chat drew particular attention because Waltz, or someone using his account, accidentally added a prominent journalist to the group.
Concerns over the security of Waltz's communications were further heightened, when it was reported on Sunday that a hacker had broken into TeleMessage's backend infrastructure and intercepted some of its users' messages.
Tech news site 404 Media said the hacker provided them with stolen material, some of which the news site was able to independently verify.
(Reporting by Raphael Satter; Editing by Bill Berkrot and Stephen Coates)
