MSRC-CVE-2026-83746 — Skype for Business Elevation of Privilege Vulnerability

Summary

Impact: Elevation of Privilege. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

What privileges could be gained by an attacker who successfully exploited the vulnerability?
An attacker would be able to delete targeted files on a system.

Security updates
7.0.2046.889 — https://support.microsoft.com/help/5131692
7.0.2046.583 — https://support.microsoft.com/help/5131693
6.0.9319.886 — https://support.microsoft.com/help/5132779

Vulnerabilities 1

High 8.1

CVE-2026-83746

Skype for Business Elevation of Privilege Vulnerability

Absolute path traversal in Skype for Business and Microsoft Lync allows an authorized attacker to elevate privileges over a network.

Microsoft Skype for Business Server 2015 CU13 Skype for Business Server 2019 CU8 Skype for Business Server Subscription Edition CU1

Oct 13, 2026

Revision history

2026-10-13 #1
Information published.

References

CVE-2026-83746 Skype for Business Elevation of Privilege Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83746
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss