CVE-2026-66305

Microsoft · Published September 8, 2026

7.1

CVSS v3.1

HIGH

Patch availableGet patch

Description

Skype for Business Spoofing Vulnerability. Use of client-side authentication in Skype for Business allows an authorized attacker to perform spoofing over a network.

Affected Products

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

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N/E:U/RL:O/RC:C