Yemen war plan leak to journalist on Signal — what we do (and don't) know

Federal laws, classified info, and consequences are questioned after officials leaked military attack details on Signal app.

The revelation that U.S. President Donald Trump's most senior national security officials posted the specifics of a military attack to a chat group that included a journalist hours before the attack took place in Yemen has raised many questions.

Among them is whether federal laws were violated, if classified information was exposed on the commercial messaging app, and whether anyone will face consequences for the leaks.

Here's what we know so far, and what we don't know.

Known: Signal is a publicly available app that provides encrypted communications, but it can be hacked. It is not approved for carrying classified information.

On March 14, one day before the strikes, the U.S. Defence Department cautioned personnel about the vulnerability of Signal, specifically that Russia was attempting to hack the app, according to a U.S. official, who was not authorised to speak to the press and spoke on the condition of anonymity.

One known vulnerability is that malicious actors, if they have access to a person's phone, can link their own device to the user's Signal — and essentially monitor messages remotely in real time.

Not known: How frequently the administration and the defence department use Signal for sensitive government communications, and whether those on the chat were using unauthorised personal devices to transmit or receive those messages.