CVE-2026-20959: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Microsoft Microsoft SharePoint Enterprise Server 2016
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.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20959) in Microsoft SharePoint Enterprise Server 2016 (version 16.0.0) is classified as CWE-79, indicating improper neutralization of input during web page generation leading to cross-site scripting. An authorized attacker with limited privileges can exploit this vulnerability by tricking a user into interacting with crafted content, potentially enabling spoofing attacks over the network. The CVSS v3.1 base score is 4.6 (medium), reflecting network attack vector, low complexity, required privileges, and user interaction. The vulnerability does not impact availability and has confirmed remediation available.
Potential Impact
Successful exploitation could allow an authorized attacker to perform spoofing attacks by injecting malicious scripts into web pages generated by SharePoint. This may lead to limited confidentiality and integrity impacts, such as executing unauthorized scripts in the context of a user session. There is no known impact on system availability. No known exploits are reported in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. Administrators should apply the official Microsoft update for SharePoint Enterprise Server 2016 version 16.0.0 to remediate this issue. Since this is not a cloud service, manual patching is required. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-20959: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Microsoft Microsoft SharePoint Enterprise Server 2016
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20959) in Microsoft SharePoint Enterprise Server 2016 (version 16.0.0) is classified as CWE-79, indicating improper neutralization of input during web page generation leading to cross-site scripting. An authorized attacker with limited privileges can exploit this vulnerability by tricking a user into interacting with crafted content, potentially enabling spoofing attacks over the network. The CVSS v3.1 base score is 4.6 (medium), reflecting network attack vector, low complexity, required privileges, and user interaction. The vulnerability does not impact availability and has confirmed remediation available.
Potential Impact
Successful exploitation could allow an authorized attacker to perform spoofing attacks by injecting malicious scripts into web pages generated by SharePoint. This may lead to limited confidentiality and integrity impacts, such as executing unauthorized scripts in the context of a user session. There is no known impact on system availability. No known exploits are reported in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. Administrators should apply the official Microsoft update for SharePoint Enterprise Server 2016 version 16.0.0 to remediate this issue. Since this is not a cloud service, manual patching is required. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.340Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668ae6a60475309f9ae268
Added to database: 1/13/2026, 6:11:50 PM
Last enriched: 4/3/2026, 12:53:03 PM
Last updated: 5/10/2026, 2:42:37 PM
Views: 105
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