CVE-2026-81387: CWE-497: Exposure of Sensitive System Information to an Unauthorized Control Sphere in Microsoft Microsoft 365 Apps for Enterprise
Description
Exposure of sensitive system information to an unauthorized control sphere in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
CVSS v3.1
Score 5.5medium
Affected software
Microsoft
Microsoft 365 Apps for Enterprise
Microsoft
Microsoft Excel 2016
Microsoft
Microsoft Office 2016
Microsoft
Microsoft Office 2019
Microsoft
Microsoft Office 365 for Mac
Microsoft
Microsoft Office LTSC 2021
Microsoft
Microsoft Office LTSC 2024
Microsoft
Microsoft Office LTSC for Mac 2021
Microsoft
Microsoft Office LTSC for Mac 2024
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-81387) involves exposure of sensitive system information in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. An unauthorized attacker can disclose information locally due to this flaw. The CVSS 3.1 vector indicates the attack requires local access with low complexity, no privileges, and user interaction. The impact is confidentiality loss without integrity or availability impact. Microsoft has published an official fix for this vulnerability.
Potential Impact
The vulnerability allows an unauthorized local attacker to disclose sensitive system information, potentially aiding further attacks or reconnaissance. There is no impact on integrity or availability. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided patches as detailed in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81387. Since this is a local attack requiring user interaction, applying the patch mitigates the risk effectively.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-26T18:46:26.215Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Is Cloud Service
- true
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81387","vendor":"Microsoft"}]
Threat ID: 6aa0456dacd9273b49faffd4
Added to database: 09/08/2026, 17:27:09 UTC
Last enriched: 10/14/2026, 22:07:47 UTC
Last updated: 10/23/2026, 15:10:15 UTC
Views: 39
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