CVE-2026-20959
Microsoft SharePoint Server Spoofing Vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Microsoft SharePoint Server Spoofing Vulnerability
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.
- Record
CVE-2026-20959- CVSS 3.1
- 4.6 Medium
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 - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-2101
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.
- Record
EUVD-2026-2101- CVSS 3.1
- 4.6 Medium
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-wvw4-rf55-ww3f
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft...
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.
- Record
GHSA-wvw4-rf55-ww3f- CVSS 3.1
- 4.6 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-20959- CVSS 3.1
- 4.6 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20959 is a medium vulnerability (CVSS 4.6) in Microsoft Sharepoint Server, published January 13, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 7.68%, the 94th percentile. No source names a fixed version.