CVE-2021-1517: Cisco Webex Meetings and Webex Meetings Server Multimedia Sharing Security Bypass Vulnerability

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-04 · updated 2026-06-17
Weakness: CWE-693

Description

A vulnerability in the multimedia viewer feature of Cisco Webex Meetings and Cisco Webex Meetings Server could allow an authenticated, remote attacker to bypass security protections. This vulnerability is due to unsafe handling of shared content within the multimedia viewer feature. An attacker could exploit this vulnerability by sharing a file through the multimedia viewer feature. A successful exploit could allow the attacker to bypass security protections and prevent warning dialogs from appearing before files are offered to other users.

Affected products

Cisco WebEx WRF Player: 41.3.5
Cisco WebEx Meetings Server: before 3.0; 3.0, 3.0-maintenance_release1, 3.0-maintenance_release2, 3.0-maintenance_release3, 4.0, 4.0-maintenance_release1 (+4) — fixed in 3.0

How to fix

Upgrade to a fixed version: Cisco WebEx Meetings Server 3.0. Check the vendor advisory for mitigations.

References

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