Former Fox News host Tucker Carlson said the NSA hacked into his Signal account

> Tucker Carlson was called to Washington because of a possible interview with Putin.

> Former Fox News host Tucker Carlson said the US National Security Agency hacked into his Signal account and read correspondence about a planned interview with Russian President Vladimir Putin.

> According to the presenter, he received a call and was summoned to Washington to clarify the situation. When he arrived, the question was asked if he was planning a trip to meet with Putin.

> “How did you know, I didn’t tell anyone. Not at all. Not to my brother, not to my wife, not to anyone at all. How did you know? Because the NSA hacked into your correspondence with another person with whom you discussed this,” Carlson said.

> The day before, RT editor-in-chief Margarita Simonyan said that Tucker Carlson wants to interview Russian President Vladimir Putin.

How so? I imagine this is just a side-channel attack against Signal, i.e the phone's OS got malware and then intercepted Signal messages, not an attack on the Signal protocol itself.