CVE-2026-97009: CWE-122: Heap-based Buffer Overflow in Microsoft Microsoft 365 Apps for Enterprise
Description
CVE-2026-97009 is a heap-based buffer overflow vulnerability in Microsoft Office Excel within Microsoft 365 Apps for Enterprise. It allows an unauthorized attacker to execute code locally on affected systems. The vulnerability has a high severity rating with a CVSS score of 7.8. An official fix is available from Microsoft to address this issue.
CVSS v3.1
Score 7.8high
Affected software
Microsoft
Microsoft 365 Apps for Enterprise
Microsoft
Microsoft Office LTSC 2021
Microsoft
Microsoft Office LTSC 2024
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-97009) involves a heap-based buffer overflow in Microsoft Office Excel component of Microsoft 365 Apps for Enterprise. Exploitation could enable an unauthorized attacker to execute arbitrary code locally. The CVSS 3.1 vector indicates local attack vector with low complexity, no privileges required, but user interaction is needed. The impact includes high confidentiality, integrity, and availability impact. Microsoft has published an official fix for this vulnerability.
Potential Impact
Successful exploitation allows local code execution by an unauthorized attacker, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided security updates as soon as possible. Since this is a cloud service, Microsoft manages remediation for the cloud-hosted components. Refer to the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97009 for detailed patching instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-23T20:52:28.738Z
- 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-2026-97009","vendor":"Microsoft"}]
Threat ID: 6ace858a2cdf04f656a01860
Added to database: 10/13/2026, 19:24:58 UTC
Last enriched: 10/13/2026, 23:33:25 UTC
Last updated: 10/13/2026, 23:33:25 UTC
Views: 2
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