CVE-2026-66302: Microsoft Skype For Business Server

Critical severity, CVSS 9.8. EPSS: 1% chance of exploitation in the next 30 days.

External control of file name or path in Skype for Business allows an unauthorized attacker to execute code over a network.

Affected products

• Microsoft Skype For Business Server: version 2015 only; version 2019 only
• Microsoft Skype For Business Server Subscription Edition: version 7.0.2046.849 only

Published 2026-09-08. Last modified 2026-09-16.