MicrosoftCVE-2026-66305
Microsoft Skype for Business: spoofing
High7.1CVE-2026-66305 · Published Sep 8, 2026 · updated Sep 16, 2026
Use of client-side authentication in Skype for Business allows an authorized attacker to perform spoofing over a network.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Skype for Business Server 2015 CU13 Product | >= 9319.0, < 6.0.9319.885 | 6.0.9319.885 |
| Skype for Business Server 2019 CU8 Product | >= 2046.0, < 7.0.2046.569 | 7.0.2046.569 |
| Skype for Business Server Subscription Edition CU1 Product | >= 2046.0, < 7.0.2046.879 | 7.0.2046.879 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-603
More Microsoft advisories
All Microsoft| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 8 | Microsoft Skype for Business: spoofing | High8.3 | 6.0.9319.885+2 more |
| Sep 8 | Microsoft Skype for Business: cross-site scripting | Medium6.5 | 6.0.9319.885+2 more |
| Sep 8 | Microsoft Skype for Business: information disclosure | Medium6.5 | 6.0.9319.885+2 more |
| Sep 8 | Microsoft Skype for Business: integer overflow | High7.5 | 6.0.9319.885+2 more |
| Sep 8 | Microsoft Skype for Business: out-of-bounds read | Medium6.5 | 6.0.9319.885+2 more |
| Sep 8 | Microsoft Skype for Business: cross-site scripting | Medium6.5 | 6.0.9319.885+2 more |