CVE-2026-66305
highUse of client-side authentication in Skype for Business allows an authorized attacker to perform spoofing over a network.
Vendor / product: Microsoft — skype for business server
Use of client-side authentication in Skype for Business allows an authorized attacker to perform spoofing over a network.
CVSS
7.1
7.1 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N Severity source: NVD CVSS v3.1 (secure@microsoft.com)
Timeline (UTC)
Published: 2026-09-08 19:18
Modified: 2026-09-16 19:24
NVD status: Analyzed
Last synced 1 day ago
Verified against the source API 2026-10-27 06:52 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
microsoft / skype_for_business_server 2015, 2019
microsoft / skype_for_business_server_subscription_edition 7.0.2046.849
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66305
Patch / mitigation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66305
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66305 secure@microsoft.com
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:52 UTC · record ↗