Out-of-bounds Read in Microsoft Skype For Business Server
CVE-2026-66308
Out-of-bounds read in Skype for Business allows an authorized attacker to deny service over a network.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.011 (66.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- Microsoft Skype For Business Server — versions 2015, 2019
- Microsoft Skype For Business Server 2015 Cu13
- Microsoft Skype For Business Server Subscription Edition — versions 7.0.2046.849
Weakness classification (CWE)
References
- Skype for Business and Lync Denial of Service Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-66308?
- CVE-2026-66308 is a medium-severity vulnerability in Microsoft Skype For Business Server, classified under Out-of-bounds Read. CVSS score: 6.5/10. Published 2026-09-08.
- How severe is CVE-2026-66308?
- Medium severity. CVSS v3 base score is 6.5 out of 10.