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CVE-2026-109456 Microsoft Office SharePoint Spoofing Vulnerability

4.6 mediumEPSS 0.5%

Medium (4.6) in microsoft microsoft sharepoint server subscription edition. EPSS 0.5% estimated probability of exploitation activity in the next 30 days.

On this page
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.

Severity

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
EPSS
0.5% estimated probability of exploitation activity in the next 30 days; 40th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-10. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-79 Improper Neutralization of Input During Web Page Generation (Cross-site Scripting)
OWASP Top 10
A05:2025 Injection
Published
Modified
Assigned by
microsoft (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

  • microsoft:microsoft sharepoint server subscription edition

Versions

From the CNA's record in the CVE List.

ProductAffected
Microsoft SharePoint Server Subscription Editionfrom 16.0.0 before 16.0.20326.20278

Attack patterns (CAPEC)

  • CAPEC-63 Cross-Site Scripting (XSS) Likelihood: High · Severity: Very High
  • CAPEC-85 AJAX Footprinting Likelihood: High · Severity: Low
  • CAPEC-209 XSS Using MIME Type Mismatch Severity: Medium
  • CAPEC-588 DOM-Based XSS Likelihood: High · Severity: Very High
  • CAPEC-591 Reflected XSS Likelihood: High · Severity: Very High
  • CAPEC-592 Stored XSS Likelihood: High · Severity: Very High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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