Vulnerability in Microsoft Skype For Business Server 2015 Cu13

CVE-2026-66305

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

CVSS v3 metric

CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-66305?
CVE-2026-66305 is a high-severity vulnerability in Microsoft Skype For Business Server 2015 Cu13, classified under CWE-603. CVSS score: 7.1/10. Published 2026-09-08.
How severe is CVE-2026-66305?
High severity. CVSS v3 base score is 7.1 out of 10.