Vulnerability · Published Jan 13, 2026 · Assigned by microsoft
CVE-2026-20959Microsoft SharePoint Server Spoofing Vulnerability
Medium 4.6
In plain English
A medium-severity cross-site scripting in Microsoft SharePoint Enterprise Server 2016 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 7.7% (higher than 95% of all known vulnerabilities).
Severity (CVSS 3.1)4.6Medium
Exploit odds (30 days)7.7%top 5.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft SharePoint Enterprise Server 2016 | 16.0.0 – before 16.0.5535.1001 |
| Microsoft | Microsoft SharePoint Server 2019 | 16.0.0 – before 16.0.10417.20083 |
| Microsoft | Microsoft SharePoint Server Subscription Edition | 16.0.0 – before 16.0.19127.20442 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C
References
- Microsoft SharePoint Server Spoofing Vulnerability vendor-advisory, patch