CVE-2026-20959 (GCVE-0-2026-20959)

Vulnerability from cvelistv5 – Published: 2026-01-13 17:56 – Updated: 2026-01-13 21:42
VLAI?
Title
Microsoft SharePoint Server Spoofing Vulnerability
Summary
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 ?
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
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
Microsoft Microsoft SharePoint Enterprise Server 2016 Affected: 16.0.0 , < 16.0.5535.1001 (custom)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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