Is Signal safe?

 Signal, once a niche messaging service for the privacy-minded, is currently the most downloaded app in the United States, unseating perennially popular social media and gaming apps. Its newfound popularity is due to a convergence of reasons, including Whats App’s changing policies, violence at the Capitol that led many tech companies to de-platform Trump, and a viral tweet from the world’s wealthiest man.

On January 7, Tesla founder Elon Musk tweeted “Use Signal” and sent the valuation of the wrong company, tiny health care technology firm Signal Advance, beyond its wildest expectations. Musk had been referring to the unrelated encrypted messaging outfit, which also benefited immensely from the tweet.

Signal has seen millions of new users flock to its app over the last few months, but is it safe? We reached out to three security experts to learn more about Signal and how it deals with your data.

WhatsApp took a hit in January when it asked users to consent to sharing their data with Facebook, who acquired the company in 2014, or lose access to their chats.

Just ten days later, Signal went down as it struggled to deal with the millions of new users that had signed up to the messaging app. Thankfully, the outage didn’t last long and Signal later tweeted that it had expanded its capacity to accommodate the influx of new users.

Months have passed now and, though it has extended its deadline, WhatsApp still wants you to agree to its new terms. We’ve already looked at whether WhatsApp is safe, but is Signal a safe alternative if you’re considering jumping ship? Here’s what three security experts said…

Signal and end-to-end encryption

“Signal is an encrypted messaging app and for many, is a secure way to communicate with friends and family because of its end-to-end encryption,” Chief Scientist and McAfee Fellow, Raj Samani told Trusted Reviews.

“What this means is that messages sent on the app are encrypted, so that only the intended receiver’s device can actually read the message,” explained Samani.

“The same applies to any exchanges on the app via voice calls. In short, this keeps third party services and even Signal itself from seeing the content of messages, making it a popular choice for people wanting to use a messaging app with enhanced privacy and security.”

Signal vs other messaging services

“Signal saw a surge in downloads after Whats-app announced it would require data sharing with Facebook, its parent company, and also after notable endorsements from particular users,” said Samani.

“As Signal is not owned by a big tech conglomerate and operates as an independent non-profit, this can be a benefit for some users seeking greater privacy”.

“Signal has always been more clunky than WhatsApp,” said Koivunen. “It shows that Signal doesn’t have the vast resources and the UX expertise that Facebook possesses. Similarly, Signal’s systems nearly gave in when there was a huge surge to register for their service last week. Signal has deliberately been designed to not backup in the cloud. WhatsApp message archives get backed up to iCloud or Google Drive in clear text if user so allows”.

Signal and your data

One of the biggest differentiators between Signal and WhatsApp is who run the apps.

“As a non-profit and privacy focused app, Signal claims to have no financial motivations to share its user’s private information,” assured Samani. “The only information Signal claims to collect is the telephone number but even that it cannot link back to your identity.”

Of course, it isn’t just Signal’s security you need to worry about. Hackers can intercept your data through other apps, reminds Principal Security Researcher at Kaspersky, David Emm.

So, should you move your WhatsApp chats to Signal?

“The majority of features on Signal are also present on WhatsApp, making it like-for-like in terms of its user offering”, said Samani. “But, with Signal’s privacy stance it is widely regarded as one of the safest messaging apps currently available. And, while WhatsApp also features encryption and both apps use Signal’s encryption protocol, Signal’s is fully open source, which means that security researchers can regularly examine the platform for security vulnerabilities.”

The important part is that you do your own research before downloading any new app.

“Those looking to make the move to Signal are likely to do so based on the app’s encryption. It should be common knowledge that WhatsApp doesn’t look at the content of chats on the platform, just like Signal. However, it is worth verifying its privacy policy to determine if the data collected is acceptable.”