CVE-2026-20955: CWE-822: Untrusted Pointer Dereference in Microsoft Microsoft 365 Apps for Enterprise
Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20955) is classified under CWE-822 (Untrusted Pointer Dereference) and affects Microsoft Office Excel within Microsoft 365 Apps for Enterprise version 16.0.1. It allows an attacker without privileges to execute code locally by exploiting improper handling of pointers. The CVSS v3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability has been officially published and a patch is available.
Potential Impact
Successful exploitation of this vulnerability could result in local code execution by an unauthorized attacker, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. However, exploitation requires local access and user interaction. No known exploits are currently reported in the wild.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official update from Microsoft for Microsoft 365 Apps for Enterprise version 16.0.1 to remediate this issue. Since this is not a cloud service, remediation depends on applying the patch on affected endpoints.
CVE-2026-20955: CWE-822: Untrusted Pointer Dereference in Microsoft Microsoft 365 Apps for Enterprise
Description
Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20955) is classified under CWE-822 (Untrusted Pointer Dereference) and affects Microsoft Office Excel within Microsoft 365 Apps for Enterprise version 16.0.1. It allows an attacker without privileges to execute code locally by exploiting improper handling of pointers. The CVSS v3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability has been officially published and a patch is available.
Potential Impact
Successful exploitation of this vulnerability could result in local code execution by an unauthorized attacker, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. However, exploitation requires local access and user interaction. No known exploits are currently reported in the wild.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official update from Microsoft for Microsoft 365 Apps for Enterprise version 16.0.1 to remediate this issue. Since this is not a cloud service, remediation depends on applying the patch on affected endpoints.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.340Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668ae5a60475309f9ae244
Added to database: 1/13/2026, 6:11:49 PM
Last enriched: 4/3/2026, 12:52:30 PM
Last updated: 5/10/2026, 9:11:56 AM
Views: 209
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