Improper Input Validation

Summary

vulnerability within the Multimedia Viewer feature of Cisco Webex Meetings could allow an authenticated, remote attacker to bypass security protections. The vulnerability is due to missing security warning dialog boxes when a room host views shared multimedia files. An authenticated, remote attacker could exploit this vulnerability by using the host role to share files within the Multimedia sharing feature and convincing a former room host to view that file. A warning dialog normally appears cautioning users before the file is displayed; however, the former host would not see that warning dialog, and any shared multimedia would be rendered within the user's browser. The attacker could leverage this behavior to conduct additional attacks by including malicious files within a targeted room host's browser window.