Security and Privacy Issues with Zoom
With the increase of employees turning to remote work during the pandemic, companies have been relying on video conferencing platforms, such as Zoom, for regular meetings and communication between employees. According to Check Point, there have been 1,700 new Zoom domains registered since the pandemic began, a quarter of these domains were registered just in the past week. Attackers have noticed the spike in users, which raises concerns for businesses that use Zoom. There have also been an increase in privacy concerns due to the sensitivity of information that is now being transferred over the platform.
In Zoom conferences, anyone with the right link can enter a teleconference and share a screen, even without a Zoom account. There have been new complaints about users being Zoom- bombed, which is when unwanted guests intrude on video meetings for malicious purposes. Recently, two online classrooms in Massachusetts were interrupted by an anonymous attacker during instruction. During the online classroom meeting, an unidentified person yelled profanity during instruction before shouting the teacher’s home address. Another classroom was disturbed by an intruder who displayed his hate tattoos to all the students and the teacher.
There have been several of these intrusions on online classrooms as well as in business conferences. Users have made several reports of conferences being interrupted by graphic images and threatening language. As a result, many schools and businesses have completely switched to other platforms, such as Microsoft Teams and Google Hangouts.
This is not the first time Zoom had security flaws in their platform. In 2019, security researcher Jonathan Leitschuh found a vulnerability in the Mac Zoom Client. When a user downloaded the Zoom app, Zoom silently installed a hidden web server on the device without the user’s permission. This web server allowed websites to join in on any Zoom call when their video camera was activated, a flaw that also impacted Ringcentral. This web server remained on the device, even if the Zoom app was uninstalled. At the time, there were 750,000 companies using Zoom for business purposes that were put at risk due to this vulnerability. Apple and Zoom have since resolved this issue for Mac users.
Another vulnerability found by Check Point researchers was quickly fixed by Zoom. Zoom calls had a randomly generated ID number between 9 and 11 digits long that allowed users to locate and join a specific call. Check Point researchers were able to predict which were valid meetings and join in on them. Zoom allows video conferences to have hundreds of participants, so it was easy for an attacker to join a call unnoticed. Zoom recently changed the randomly generated numbers into a more “cryptographically strong” one, added more digits to meeting ID numbers, and made requiring passwords default for future meetings.
Allowing vulnerable servers to run on devices makes it easier for attackers to intrude on conferences. While removing the vulnerable web server was a big help, attackers are still able to access meetings over Zoom. Officials warn businesses and individuals about an increase in phishing emails for attackers to enter and exploit networks. These can be especially detrimental to remote workers, as cybersecurity and information security is often weaker at home than in the office. Check Point researchers confirmed that at least 70 of the newly created Zoom domains were being used maliciously, often as phishing websites in order to steal unsuspecting users’ personal information.
Users have also expressed concerns over Zoom’s privacy flaws. Zoom allows hosts to see if participants have been on a different screen for more than 30 seconds. Additionally, for paid subscribers, a host can record the meeting and have access to text files of any active chats that take place during the meeting. The host can then save these files to the cloud where it can be shared and accessed by other authorized users.
Earlier this week, there were questions raised about Zoom sharing customer data with Facebook, even if the users did not have a Facebook account. The Zoom app notified Facebook when the user opened the app, details on the user’s device including where the device is located and phone carrier, and a unique advertiser identifier created by the user’s device. With this information, companies could target a user with specific advertisements. This practice is not new and is fairly common with major applications. Several apps use Facebook’s Software Development Kit (SDK) to implement features on their apps, which ultimately sends information to Facebook. This concern has since been addressed and fixed by Zoom. Zoom now enables users to log in with Facebook via browser, rather than through the Facebook SDK.
The privacy of Zoom calls has particularly raised concerns for parents whose children are now using Zoom for education. However, Zoom claimed that their service for schools complies with federal laws on educational and student privacy.
Many officials are worried that Zoom has not taken any precautions when dealing with the spiked volume of users. The New York Attorney General warns that the existing security practices may not translate well with the volume and sensitivity of data now being transferred through Zoom.
Zoom’s cloud meeting app is now one of the most popular apps being downloaded on iPhones. Here are some tips to protecting your Zoom conferences:
- Keep conferencing private rather than public and refrain from posting the links to your conferences on social media
- Keep the screen- sharing feature only to the host
- Lock meetings when they are in session so no new participants can join
- Mute participants and disable the file transfer feature when it is not in use
