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.

The clone, TeleMessage, was the subject of a reported hack in which the contents of some direct messages and group chats were stolen.

A hacker breached TeleMessage, a company that sells a modified version of Signal to the US government. Mike Waltz was spotted using it last week.