Clubhouse's Security and Privacy Lag Behind Its Explosive Growth

By Lily Hay Newman

In recent months, the audio-based social media app Clubhouse has emerged as Silicon Valley's latest disruptive darling. The format feels familiar: part Twitter, part Facebook Live, part talking on the phone. But as Clubhouse continues to expand, its security and privacy failings have come under increased scrutiny—and left the company scrambling to correct problems and manage expectations.

Clubhouse, still in beta and available only on iOS, offers its users “rooms” that are essentially group audio chats. They can also be set as public addresses or panel discussions where some users are “speakers” and the rest are audience members. The platform reportedly has over 10 million users and is valued at $1 billion. Since last year it has been an invite-only haven for Silicon Valley elite and celebrities, including an Elon Musk appearance earlier this month. But the company has struggled both with concrete security issues and more ephemeral questions around how much privacy its users should expect. 

“With smaller, newer social media platforms, we should be on our guard about our data, especially when they go through huge growth it tests a lot of the controls,” says security researcher Robert Potter. “Things you might have gotten away with with only 100,000 people on the platform—you increase those numbers tenfold and the level of exposure goes up, the threat goes up, the number of people probing your platform goes up.”

Recent security concerns about Clubhouse run the gamut from vulnerabilities to questions about the app's underlying infrastructure. A little over a week ago, researchers from the Stanford Internet Observatory put a spotlight on the platform when they found that the app was transmitting users' Clubhouse identifiers and chatroom identity numbers unencrypted, meaning that a third party could have potentially tracked your actions in the app. The researchers further pointed out that some of Clubhouse's infrastructure is run by a Shanghai-based firm and it seemed that the app's data was traveling through China at least some of the time—potentially exposing users to targeted or even widespread Chinese government surveillance. Then, on Sunday, Bloomberg confirmed that a third-party website was scraping and compiling audio from Clubhouse discussions. Early Monday, further revelations followed that Clubhouse discussions were being scraped for an unaffiliated Android app, allowing users on that operating system to listen along in real-time. 

Potter, one of the researchers who investigated the different Clubhouse data scraping projects, explains that these apps and websites didn't seem malicious; they just wanted to make Clubhouse content available to more people. But the developers were only able to do so because Clubhouse didn't have anti-scraping mechanisms that could have stopped that. Clubhouse didn't limit how many rooms a single account could stream from at once, for example, so anyone could create an application programming interface to stream every public channel at the same time.

More mature social networks like Facebook have more developed mechanisms for locking their data down, both to prevent user privacy violations and to defend the data they hold as an asset. But even they can still have potential exposures from creative scraping techniques.

Clubhouse has also come under scrutiny for its aggressive collection of users' contact lists. The app strongly encourages all users to share their address book data so Clubhouse can help you make connections with people you know who are already on the platform. It also requires you to share your contact list in order to invite other people to the platform, since Clubhouse is still invite-only, which contributes to a sense of exclusivity and privacy. Numerous users have pointed out, though, that when you go to invite others, the app also makes suggestions based on what phone numbers in your contacts are also in the contacts of the largest number of Clubhouse users. In other words, if you and your local friends all use the same florist, doctor, or drug dealer, they very well could show up on your list of suggested people to invite.