CVE-2026-50678: CWE-122: Heap-based Buffer Overflow in Microsoft Microsoft 365 Apps for Enterprise
CVE-2026-50678 is a heap-based buffer overflow vulnerability in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. This flaw allows an unauthorized local attacker to disclose information. The vulnerability has a medium severity with a CVSS score of 6.6. An official fix is available from Microsoft. The affected version explicitly includes 16.0.1. Microsoft manages remediation for this cloud-hosted service, and users should apply the official update as advised.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-50678) involves a heap-based buffer overflow in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It allows an unauthorized attacker with local access to potentially disclose information. The CVSS 3.1 vector indicates low attack complexity, no privileges required, but user interaction is needed. The impact includes limited confidentiality and integrity loss, with high availability impact. Microsoft has released an official fix and manages remediation for this cloud service. The affected version is 16.0.1.
Potential Impact
An unauthorized local attacker could exploit this heap-based buffer overflow to disclose information. The vulnerability impacts confidentiality and integrity to a limited extent and has a high impact on availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users should follow the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50678 to ensure their environment is updated and protected.
CVE-2026-50678: CWE-122: Heap-based Buffer Overflow in Microsoft Microsoft 365 Apps for Enterprise
Description
CVE-2026-50678 is a heap-based buffer overflow vulnerability in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. This flaw allows an unauthorized local attacker to disclose information. The vulnerability has a medium severity with a CVSS score of 6.6. An official fix is available from Microsoft. The affected version explicitly includes 16.0.1. Microsoft manages remediation for this cloud-hosted service, and users should apply the official update as advised.
CVSS v3.1
Score 6.6medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-50678) involves a heap-based buffer overflow in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It allows an unauthorized attacker with local access to potentially disclose information. The CVSS 3.1 vector indicates low attack complexity, no privileges required, but user interaction is needed. The impact includes limited confidentiality and integrity loss, with high availability impact. Microsoft has released an official fix and manages remediation for this cloud service. The affected version is 16.0.1.
Potential Impact
An unauthorized local attacker could exploit this heap-based buffer overflow to disclose information. The vulnerability impacts confidentiality and integrity to a limited extent and has a high impact on availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users should follow the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50678 to ensure their environment is updated and protected.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-05T14:35:07.080Z
- 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-2026-50678","vendor":"Microsoft"}]
Threat ID: 6a566f7968715ace43e6b9dc
Added to database: 07/14/2026, 17:18:49 UTC
Last enriched: 07/15/2026, 01:18:12 UTC
Last updated: 07/15/2026, 01:18:12 UTC
Views: 3
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