CVE-2026-66805 (GCVE-0-2026-66805)

Vulnerability from cvelistv5 – Published: 2026-08-11 17:07 – Updated: 2026-08-31 20:07
VLAI
Title
Microsoft SharePoint Server Remote Code Execution Vulnerability
Summary
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 00:00 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
References
Impacted products
Vendor Product Version CPE status
Microsoft Microsoft SharePoint Enterprise Server 2016 Affected: 16.0.0 , < 16.0.5565.1001 (custom)
guessed Create a notification for this product.
Microsoft Microsoft SharePoint Server 2019 Affected: 16.0.0 , < 16.0.10417.20198 (custom)
guessed Create a notification for this product.
Microsoft Microsoft SharePoint Server Subscription Edition Affected: 16.0.0 , < 16.0.19725.20522 (custom)
guessed Create a notification for this product.
Date Public
2026-08-11 14:00
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.


Detection rules are retrieved from Rulezet.