CVE-2026-66806 (GCVE-0-2026-66806)

Vulnerability from cvelistv5 – Published: 2026-08-11 17:07 – Updated: 2026-08-31 20:07
VLAI
Title
Microsoft Office Word Information Disclosure Vulnerability
Summary
Off-by-one error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-11 21:00 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Microsoft Microsoft 365 Apps for Enterprise Affected: 16.0.1 , < https://aka.ms/OfficeSecurityReleases (custom)
guessed Create a notification for this product.
Microsoft Microsoft Office 2019 Affected: 19.0.0 , < https://aka.ms/OfficeSecurityReleases (custom)
guessed Create a notification for this product.
Microsoft Microsoft Office LTSC 2021 Affected: 16.0.1 , < https://aka.ms/OfficeSecurityReleases (custom)
guessed Create a notification for this product.
Microsoft Microsoft Office LTSC 2024 Affected: 16.0.0 , < https://aka.ms/OfficeSecurityReleases (custom)
guessed Create a notification for this product.
Microsoft Microsoft Word 2016 Affected: 16.0.1 , < 16.0.5565.1000 (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

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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.
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  • 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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