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CVE-2026-40421 (GCVE-0-2026-40421)

Vulnerability from cvelistv5 – Published: 2026-05-12 16:58 – Updated: 2026-08-10 15:12
VLAI
Title
Microsoft Word Information Disclosure Vulnerability
Summary
Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/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 2026-05-13 19:25 UTC
CWE
  • CWE-73 - External Control of File Name or Path
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 , < 16.0.5552.1000 (custom)
guessed Create a notification for this product.
Date Public
2026-05-12 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.
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  • 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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