Cisco has confessed to a vulnerability in its Webex Meetings Suite sites and Webex Meetings Online sites that allowed an "unauthenticated" attendee sitting on a workstation far, far away to join a "password-protected meeting without providing the meeting password".
According to the security advisory, which was rated as "High": "The vulnerability is due to unintended meeting information exposure in a specific meeting join flow for mobile applications."
This is where the user goes to the meeting link in a browser – for which the meeting ID is needed. The browser then launches the Webex app, and it is within this flow that the vulnerability could be exploited.
They wouldn't have snuck in unnoticed, however.
"A successful exploit could allow the unauthorized attendee to join the password-protected meeting. The unauthorized attendee will be visible in the attendee list of the meeting as a mobile attendee," said Cisco.
Vulnerable products include Cisco's Webex Meetings Suite and Webex Meetings Online site releases earlier than 39.11.5 and 40.1.3. The on-premises Cisco Webex Meetings Server (which incidentally will be end of life in July) is not affected.
There are no workarounds, Cisco said, but the bug has been fixed and users will not need to update their mobile or desktop Webex applications.
The vulnerability was discovered as a result of a support case, and according to the advisory, although there was no previous public disclosure: "Cisco PSIRT [Product security Incident Response Team] is aware of active use of the vulnerability that is described in this advisory."
As vulnerabilities go, it could be worse. Having said that, unauthorised attendance at an online meeting could have consequences, such as employees learning management secrets, industrial espionage, insider trading, or worse.
Cisco also released a batch of security updates earlier this month – including one for Webex Video Mesh. ®