CVE-2017-11786: Microsoft Lync

High severity, CVSS 8.8. EPSS: 9.4% chance of exploitation in the next 30 days.

Skype for Business in Microsoft Lync 2013 SP1 and Skype for Business 2016 allows an attacker to steal an authentication hash that can be reused elsewhere, due to how Skype for Business handles authentication requests, aka "Skype for Business Elevation of Privilege Vulnerability."

Affected products

• Microsoft Lync: version 2013 only
• Microsoft Skype For Business: version 2016 only

Published 2017-10-13. Last modified 2026-06-17.