CVE-2026-45456: CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') in Microsoft Microsoft 365 Apps for Enterprise
CVE-2026-45456 is a high-severity vulnerability in Microsoft 365 Apps for Enterprise involving type confusion, which allows unauthorized local code execution. The issue arises from accessing resources using incompatible types. An official fix is available from Microsoft, and the vendor manages remediation for this cloud-hosted service.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-45456) in Microsoft 365 Apps for Enterprise is classified as CWE-843 (Access of Resource Using Incompatible Type, or type confusion). It enables an unauthorized attacker to execute code locally by exploiting improper handling of resource types. The CVSS v3.1 base score is 8.4, indicating high severity with high impact on confidentiality, integrity, and availability. Microsoft has published an official fix and manages remediation for this cloud service. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation allows an attacker with local access to execute arbitrary code, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. The vulnerability is rated high severity with CVSS 8.4, reflecting significant risk if exploited.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should ensure their Microsoft 365 Apps for Enterprise environment is updated according to Microsoft's guidance found in the vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45456.
CVE-2026-45456: CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') in Microsoft Microsoft 365 Apps for Enterprise
Description
CVE-2026-45456 is a high-severity vulnerability in Microsoft 365 Apps for Enterprise involving type confusion, which allows unauthorized local code execution. The issue arises from accessing resources using incompatible types. An official fix is available from Microsoft, and the vendor manages remediation for this cloud-hosted service.
CVSS v3.1
Score 8.4high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-45456) in Microsoft 365 Apps for Enterprise is classified as CWE-843 (Access of Resource Using Incompatible Type, or type confusion). It enables an unauthorized attacker to execute code locally by exploiting improper handling of resource types. The CVSS v3.1 base score is 8.4, indicating high severity with high impact on confidentiality, integrity, and availability. Microsoft has published an official fix and manages remediation for this cloud service. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation allows an attacker with local access to execute arbitrary code, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. The vulnerability is rated high severity with CVSS 8.4, reflecting significant risk if exploited.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should ensure their Microsoft 365 Apps for Enterprise environment is updated according to Microsoft's guidance found in the vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45456.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-05-12T16:06:43.097Z
- 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-2026-45456","vendor":"Microsoft"}]
Threat ID: 6a284cd78dd33fbd85664c01
Added to database: 6/9/2026, 5:26:47 PM
Last enriched: 6/9/2026, 10:26:53 PM
Last updated: 6/10/2026, 4:57:26 AM
Views: 3
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