CVE-2020-3126 Explained : Impact and Mitigation

A vulnerability within the Multimedia Viewer feature of Cisco Webex Meetings could allow an authenticated, remote attacker to bypass security protections.

Understanding CVE-2020-3126

This CVE involves a security vulnerability in Cisco Webex Meetings Multimedia Viewer that could be exploited by an authenticated, remote attacker.

What is CVE-2020-3126?

The vulnerability in the Multimedia Viewer feature of Cisco Webex Meetings allows a remote attacker to bypass security protections by exploiting missing security warning dialog boxes.

The Impact of CVE-2020-3126

The vulnerability enables an attacker to share malicious files within a targeted room host's browser window, potentially leading to further attacks.

Technical Details of CVE-2020-3126

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability arises due to missing security warning dialog boxes when a room host views shared multimedia files, allowing an attacker to bypass security measures.

Affected Systems and Versions

Product: Cisco Webex Meetings Multimedia Viewer
Vendor: Cisco
Affected Version: T39.3

Exploitation Mechanism

An authenticated, remote attacker can use the host role to share files within the Multimedia sharing feature.
By convincing a former room host to view the shared file, the attacker can render shared multimedia within the user's browser without the warning dialog.

Mitigation and Prevention

Steps to address and prevent the exploitation of this vulnerability.

Immediate Steps to Take

Update Cisco Webex Meetings Multimedia Viewer to the latest version.
Educate users on the risks of opening files from untrusted sources.

Long-Term Security Practices

Regularly monitor and update security patches for all software.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Apply patches and updates provided by Cisco to address the vulnerability and enhance security measures.