CVE-2026-45463: CWE-191: Integer Underflow (Wrap or Wraparound) in Microsoft Microsoft 365 Apps for Enterprise
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-45463) is an integer underflow (CWE-191) in Microsoft 365 Apps for Enterprise that results in a heap-based buffer overflow, enabling local code execution by an unauthorized attacker. The vulnerability affects version 16.0.1 and has a CVSS 3.1 base score of 8.4, indicating high severity. Microsoft has published an official fix and manages remediation for this cloud service. No known exploits have been reported in the wild.
Potential Impact
Successful exploitation allows an unauthorized attacker to execute arbitrary code locally, potentially leading to full compromise of the affected system. The vulnerability impacts confidentiality, integrity, and availability with high severity.
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 consult the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45463 for detailed patching and update instructions.
CVE-2026-45463: CWE-191: Integer Underflow (Wrap or Wraparound) in Microsoft Microsoft 365 Apps for Enterprise
Description
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
CVSS v3.1
Score 8.4high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-45463) is an integer underflow (CWE-191) in Microsoft 365 Apps for Enterprise that results in a heap-based buffer overflow, enabling local code execution by an unauthorized attacker. The vulnerability affects version 16.0.1 and has a CVSS 3.1 base score of 8.4, indicating high severity. Microsoft has published an official fix and manages remediation for this cloud service. No known exploits have been reported in the wild.
Potential Impact
Successful exploitation allows an unauthorized attacker to execute arbitrary code locally, potentially leading to full compromise of the affected system. The vulnerability impacts confidentiality, integrity, and availability with high severity.
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 consult the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45463 for detailed patching and update instructions.
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-2026-45463","vendor":"Microsoft"}]
Threat ID: 6a284cd98dd33fbd85664c60
Added to database: 6/9/2026, 5:26:49 PM
Last enriched: 6/9/2026, 10:26:29 PM
Last updated: 6/10/2026, 6:56:48 AM
Views: 4
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