CVE-2020-3440: Cisco Webex Meetings Desktop App for Windows Arbitrary File Overwrite Vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-26 · updated 2026-06-17
Weakness: CWE-22

Description

A vulnerability in Cisco Webex Meetings Desktop App for Windows could allow an unauthenticated, remote attacker to overwrite arbitrary files on an end-user system. The vulnerability is due to improper validation of URL parameters that are sent from a website to the affected application. An attacker could exploit this vulnerability by persuading a user to follow a URL to a website that is designed to submit crafted input to the affected application. A successful exploit could allow the attacker to overwrite arbitrary files on the affected system, possibly corrupting or deleting critical system files.

Affected products

Cisco Webex Meetings: before 40.8 — fixed in 40.8

How to fix

Upgrade to a fixed version: Cisco Webex Meetings 40.8. Check the vendor advisory for mitigations.

References

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