CVE-2026-66306: Microsoft Skype For Business Server

Medium severity, CVSS 6.5. EPSS: 0.9% chance of exploitation in the next 30 days.

Generation of error message containing sensitive information in Skype for Business allows an unauthorized attacker to disclose information 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.