A new analysis of TM Signal’s source code appears to show that the app sends users’ message logs in plaintext. At least one top Trump administration official used the app.

Message contents and government official contact information were obtained during the breach, 404 Media reports.

An Israeli app used by then-U.S. National Security Adviser Mike Waltz to archive chats on Signal was easily hacked and his messages accessed by a hacker, new reporting reveals, compounding security issues raised by the Trump administration’s use of the private messaging platform to discuss sensitive military business.