Cisco patched three vulnerabilities today security in Webex Meetings that allowed unauthorized remote attackers to join meetings as ghost participants.
Cisco Webex is one on-line meeting and video conferencing software that can be used to schedule and attend meetings. It provides users with presentation, screen sharing and recording capabilities.
Cisco's remote meeting platform has seen a 451% increase in usage over four months due to the COVID-19 pandemic, and is hosting approximately 4 millions meetings per day for 324 million users at its peak.
Malicious users who abused the patched security vulnerabilities could become "ghost" users and could join a meeting without being detected, IBM researchers discovered while analyzing the tool Cisco Vulnerability Partnership.
"Ghost" users are participants in a meeting that are not visible in the list of users and have not been invited to the meeting, but can listen, talk and share in the meeting.
The three errorthey also allowed attackers to remain in the Webex meeting and maintain a two-way audio connection even after administrators removed them and accessed Webex user information such as email addresses and IP addresses from the meeting "room."
IBM researchers made the following errors that allowed the attackers to:
- Participate in a Webex meeting as "Ghost" without appearing on the attendee list with full access to audio, video, chat and screen sharing features (CVE-2020-3419)
- Stay in a Webex meeting as a "Ghost" even if they are expelled from it, maintaining the audio connection (CVE-2020-3471)
- Access meeting meeting information - full names, email addresses and IP addresses even without being accepted into the call (CVE-2020-3441)
Cisco recommends that users immediately update to the latest version of Webex to secure meetings from intruders trying to exploit these vulnerabilities.
