Le Temps March 26, 2025 ANOUCH SEYDTAGHIA
Despite recent amateur use by US officials, Signal is one of the most secure messaging services, ahead of WhatsApp or Telegram. However, the app is not recommended for government use. Here's our explanation.
This is a spotlight that Signal's executives probably wouldn't have imagined: the use of the messaging app by very high-ranking officials in the US government. Since Monday, it has become known that they are communicating via this app. It was Jeffrey Goldberg, editor-in-chief of The Atlantic magazine, mistakenly added to a group, who revealed the affair. He was able to read exchanges with 18 people, including Vice President JD Vance, National Security Advisor Michael Waltz, Secretary of State Marco Rubio, Secretary of Defense Pete Hegseth, and Director of National Intelligence Tulsi Gabbard. This affair, which has triggered a political crisis in Washington, is an opportunity to take a closer look at Signal.
How does Signal work?
On the surface, it's like WhatsApp or Telegram. But Signal differs in two key ways. First, the business model, since the app is supported by a non-profit foundation based in the United States. Signal is free, without advertising or user tracking, and relies on user donations. The foundation was notably supported, through a $50 million contribution, by Brian Acton, co-founder of WhatsApp, who was disappointed with what Meta had done with it. The annual budget to run Signal is a similar amount.
The other difference from its competitors is Signal's transparent core. The messaging encryption protocol is open source, making it easily analyzeable by any external expert. Signal reportedly has between 50 and 100 million users, far fewer than the billion claimed by Telegram or WhatsApp's more than 2 billion customers.
Is Signal infallible?
Its security level is very high. "To my knowledge, the Signal protocol has never been cracked. But I know that governments are actively trying to do so, so there is no guaranteed protection forever," says Steven Meyer, director of the cybersecurity firm ZENData. "Apps like Signal and WhatsApp rely on end-to-end encryption that makes messages readable only by the sender and the recipient. It seems this technique is effective because several countries, including France, require these companies to introduce backdoors to gain access to information."
"The Signal protocol has never been cracked. But governments are actively trying to do so, so there is no guaranteed protection forever." STEVEN MEYER, CEO OF ZENDATA
"These applications are particularly vulnerable to organized crime or terrorism. It would appear that these applications are therefore very resistant to hacking," notes Jean-Marc Rickli, director of global and emerging risks at the Geneva Centre for Security Policy.
Recently, Signal CEO Meredith Whittaker defended this level of protection, saying that "end-to-end encryption is the technology we have to ensure privacy in an era of unprecedented government and corporate surveillance."
Signal is therefore very resilient. But be careful: if an outsider manages to take remote control of the phone—and many governments have the technical tools to do this—the situation changes. Because it's then relatively easy to access all of the phone's content, including the contents of messaging apps.
Another concern: the user. "The fact that a stranger could have been invited and the other members of the group didn't react also raises questions that have nothing to do with cybersecurity but with the basics of digital hygiene and common sense, which are often exploited in social engineering to hack individuals or companies," notes Jean-Marc Rickli.
How should Americans have communicated?
According to Jean-Marc Rickli, "Government officials can use such apps to exchange routine, unclassified information. But the Signal app is not approved by the U.S. government for sharing classified information. To share such information, officials or decision-makers must use sensitive, compartmentalized information facilities where smartphones are not permitted. In this case, there was a clear violation of these rules."
There was indeed negligence, confirms Steven Meyer: "Generally, at the military and government level, there are communication tools for classified exchanges that are very secure and controlled. The downside is that these systems are not very practical for everyday life. So whenever possible, people use "mainstream" alternatives. And in this area, Signal is clearly the best app," says the director of ZENData.
Steven Meyer notes that in Switzerland, the Swiss app Threema is used within the military and government to communicate on topics that are not highly confidential. For more sensitive topics, other services, inaccessible to the general public, are used.
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Article Name: Signal messaging at the heart of the storm
Publication: Le Temps
Section:International
Author: ANOUCH SEYDTAGHIA
Start Page:6
End Page:6
This message was sent to me by e-mail, from a friend, originally an article in a Swiss publication, "Le Temps" in French, translated by Google and myself to suit our blog as the scandal of the App and its usage by the highest hierarchy of the American administration for highly sensitive and classified communications continues to reverberate in the US.
As always, my many thanks to all my good friends and readers.