CVE-2026-20950: CWE-416: Use After Free in Microsoft Microsoft 365 Apps for Enterprise
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability (CWE-416) involves a use-after-free condition in Microsoft Office Excel component of Microsoft 365 Apps for Enterprise (version 16.0.1). Exploitation allows an attacker with local access and user interaction to execute arbitrary code, potentially leading to full compromise of the affected system. The CVSS v3.1 base score is 7.8, reflecting high severity with impacts on confidentiality, integrity, and availability. The vulnerability has been officially published and a patch is available from Microsoft.
Potential Impact
Successful exploitation can lead to local code execution by an unauthorized attacker, resulting in complete compromise of the affected system's confidentiality, integrity, and availability. However, exploitation requires local access and user interaction. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Microsoft 365 Apps for Enterprise version 16.0.1 to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-20950: CWE-416: Use After Free in Microsoft Microsoft 365 Apps for Enterprise
Description
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-416) involves a use-after-free condition in Microsoft Office Excel component of Microsoft 365 Apps for Enterprise (version 16.0.1). Exploitation allows an attacker with local access and user interaction to execute arbitrary code, potentially leading to full compromise of the affected system. The CVSS v3.1 base score is 7.8, reflecting high severity with impacts on confidentiality, integrity, and availability. The vulnerability has been officially published and a patch is available from Microsoft.
Potential Impact
Successful exploitation can lead to local code execution by an unauthorized attacker, resulting in complete compromise of the affected system's confidentiality, integrity, and availability. However, exploitation requires local access and user interaction. There are no known exploits in the wild at this time.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Microsoft 365 Apps for Enterprise version 16.0.1 to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.339Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668ae5a60475309f9ae238
Added to database: 1/13/2026, 6:11:49 PM
Last enriched: 4/3/2026, 12:52:02 PM
Last updated: 5/9/2026, 12:10:58 AM
Views: 89
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