What is Signal, the chat app used by US officials to share attack plans?

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What is Signal, the chat app used by US officials to share attack plans?

2025-03-26 01:17 Last Updated At：01:21

LONDON (AP) — A magazine journalist's account of being added to a group chat of U.S. national security officials coordinating plans for airstrikes has raised questions about how highly sensitive information is supposed to be handled.

Atlantic Editor-in-Chief Jeffrey Goldberg detailed a discussion that happened over the Signal messaging app hours before strikes on Iran-backed Houthi-rebels in Yemen ordered by U.S. President Donald Trump.

The National Security Council has since said the text chain “appears to be authentic" and that it is looking into how a journalist’s number was added to the chain.

Here's a look at the app in question.

It's an app that can be used for direct messaging and group chats as well as phone and video calls.

Signal uses end-to-end encryption for its messaging and calling services that prevents any third-party from viewing conversation content or listening in on calls.

In other words, messages and calls sent on Signal are scrambled and only the sender and recipient at each end will have the key to decipher them.

Signal's encryption protocol is open source, meaning that it's freely available for anyone to inspect, use or modify. The encryption protocol is also used by another popular chat service, social media company Meta's WhatsApp platform.

Encryption on Signal is turned on by default, unlike another popular messaging app, Telegram, which requires users to turn it on and does not make it available for group chats.

Signal has features that are found on other messaging apps. It allows users to host group chats with up to 1,000 people and messages can be set to automatically disappear after a certain time.

Signal touts the privacy of its service and its head defended the app's security practices on Tuesday.

“Signal is the gold standard in private comms,” Meredith Whittaker, president of Signal, said on X, without directly addressing the Atlantic report.

Experts agree Signal is more secure than conventional texting.

But it could be hacked.

Government officials have used Signal for organizational correspondence, such as scheduling sensitive meetings, but in the Biden administration, people who had permission to download it on their White House-issued phones were instructed to use the app sparingly, according to a former national security official who served in the administration.

The official, who requested anonymity to speak about methods used to share sensitive information, said Signal was most commonly used to notify someone that they should check for a classified message sent through other means.

Beyond concerns about security, Signal and other similar apps may allow users to skirt open records laws. Without special archiving software, the messages frequently aren’t returned under public information requests.

In the Atlantic article, Goldberg wrote that some messages were set to disappear after one week and some after four.

Encrypted messaging apps are increasingly popular with government officials, according to a recent Associated Press review.

State, local and federal officials in nearly every state have accounts on encrypted messaging apps, according to the review, which found many of those accounts registered to government cellphone numbers. Some were also registered to personal numbers.

The app's origins date back more than a decade, when it was set up by an entrepreneur who goes by the name Moxie Marlinspike, who was briefly head of product security at Twitter after he sold his mobile security startup to the social media company. Marlinspike merged two existing open source apps, one for texting and one for voice calls, to create Signal.

The nonprofit Signal Foundation was set up in 2018 to support the app's operations as well as “investigate the future of private communication,” according to the foundation's website. The foundation says it is a nonprofit “with no advertisers or investors, sustained only by the people who use and value it.”

The foundation's board has five members, including Brian Acton, who cofounded WhatsApp and donated $50 million to set up the foundation.

Associated Press writers Tara Copp, Aamer Madhani and Eric Tucker contributed to this report from Washington.

In their own words: Trump officials shrugging off Signal leak once decried Clinton's server

2025-03-26 13:16 Last Updated At：13:20

WASHINGTON (AP) — The attempts by President Donald Trump and top leaders of his administration to downplay a security breach that revealed military strike plans in a Signal group chat including a journalist stand in stark contrast to their reaction to Hillary Clinton's use of a home server as secretary of state.

This time, they've largely focused their ire not on sweeping potential security lapses, or punishments as a result, but on the journalist who was errantly added to the group text and reported on it: editor-in-chief for The Atlantic, Jeffrey Goldberg. Some of the text's participants who spoke out against Clinton haven't commented publicly at all about the Signal leak.

One of the chief concerns about Clinton’s email server was that it was insecure, and that sensitive information could fall into the wrong hands. But former FBI Director James Comey said in recommending that no charges be brought against Clinton that there was no evidence that her email account had been hacked by hostile actors.

Trump insisted Tuesday that no classified information was divulged in the group chat, though Goldberg wrote that messaging revealed “precise information about weapons packages, targets, and timing” of strikes in Yemen. The White House’s National Security Council has said it is investigating.

For her part, Clinton's reaction to Goldberg's reporting was one of astonishment: “You have got to be kidding me,” Clinton said in an X post that spotlighted The Atlantic article and included an eyes emoji.

Here's a look at what some of the officials in the group chat, and some of those steadfastly standing by them, are saying now versus then.

Now: “The main thing was nothing happened. The attack was totally successful,” Trump said during a meeting with a group of his ambassadors at the White House on Tuesday.

He also called his national security adviser, Michael Waltz, “a very good man” and insisted “he will continue to do a very good job,” while adding, “I think it’s very unfair how they attacked Michael" and labeling Goldberg a “total sleazebag.”

Later, in an interview with Newsmax, Trump said a Waltz aide had Goldberg’s number and “this guy ended up on the call." He also added that he felt good about what occurred. "I can only go by what I’ve been told ... but I feel very comfortable, actually.”

Then: “Hillary is the one who sent and received classified information on an insecure server, putting the safety of the American people under threat,” Trump said in an October 2016 speech in Warren, Michigan.

“The rigged system refused to prosecute her for conduct that put all of us, everybody in this room, everybody in this country at risk. Hillary Clinton went to great lengths to create a private email server and to bypass government security in order to keep her emails from being read by the public and by federal officials,” he said in a November 2016 speech in Virginia Beach, Virginia.

And, during a Florida rally in July 2016, he even urged Russian hackers to help find a batch of emails said to have vanished from Clinton’s private server. “Russia, if you’re listening, I hope you’re able to find the 30,000 emails that are missing."

Now: “I think there’s a lot in the lessons for a lot of journalists in this city who have made big names for themselves making up lies about this president,” Waltz said during Tuesday’s White House meeting with Trump and the ambassadors.

He also said of Goldberg, “This journalist, Mr. President, wants the world talking about more hoaxes.”

In a subsequent interview on Fox News Channel’s “The Ingraham Angle,” Waltz said, “I take full responsibility. I built the group.” He also contradicted Trump by saying that no staffer was responsible.

Waltz further acknowledged, “embarrassing, yes” and said, “We made a mistake. We’re moving forward.”

Then: “How is it Hillary Clinton can delete 33,000 government emails on a private server, yet President Trump gets indicted for having documents he could declassify?” Waltz posted in June 2023, referencing charges against Trump for mishandling classified documents. The case was scrapped after Trump won a second term.

Now: “Nobody was texting war plans,” Hegseth told journalists traveling with him in Hawaii on Monday. He said of Goldberg, “You’re talking about a deceitful and highly discredited so-called journalist who’s made a profession of peddling hoaxes.”

Then: “Any security professional, military, government or otherwise, would be fired on the spot for this type of conduct and criminally prosecuted for being so reckless with this kind of information," Hegseth, then a regular contributor for Fox News Channel, said of Clinton's emails on the network in 2016.

That same year, Hegseth asked on Fox News, “How damaging is it to your ability to recruit or build allies with others when they are worried that our leaders may be exposing them because of their gross negligence or their recklessness in handling information?”

In another 2016 Fox News segment, Hegseth said, “If it was anyone other than Hillary Clinton, they would be in jail right now for what has been done. Because the assumption is, in the intelligence community, if you are using unclassified means, there is the potential for, and likelihood, that foreign governments are targeting those accounts and gathering intelligence from them."

Now: No public comment on the Signal group chat.

Then: “Nobody is above the law, not even Hillary Clinton – even though she thinks she is," Rubio told Fox News in January 2016.

The previous year in a Fox News interview, Rubio referred to the same emails when he said, “What they did is reckless — it’s complete recklessness and incompetence.”

Now: No public comment on the Signal leak.

Then: Miller posted in 2022: “One point that doesn’t get made enough about Hillary’s unsecured server illegally used to conduct state business (obviously created to hide the Clintons’ corrupt pay-for-play): foreign adversaries could easily hack classified ops & intel in real time from other side of the globe.”

Now: “My communications, to be clear, in a Signal message group were entirely permissible and lawful and did not include classified information," Ratcliffe said at a Tuesday congressional hearing.

Then: On Fox News in 2018, Ratcliffe suggested of officials who mishandle sensitive information: “It’s always a good thing that we see that there is investigation and prosecution of folks if they’re not handling that information appropriately.”

Now: “There’s a difference between inadvertent release versus careless and sloppy, malicious leaks of classified information,” Gabbard said at the same congressional hearing.

Then: Gabbard posted on X earlier this month, “Any unauthorized release of classified information is a violation of the law and will be treated as such.”