Junglewise Threat Intelligence

CVE-2026-68815: Microsoft Office Excel heap-based buffer overflow

CVE-2026-68815 · Severity: high · CVSS 7.8 · Published 2026-08-11

Technologies: Microsoft Office Excel. Vendors: Microsoft.

Executive brief

Microsoft Office Excel is a widely-used spreadsheet application employed across organizations for data analysis and financial modeling. A heap-based buffer overflow vulnerability allows a local attacker to execute arbitrary code on a user's system, potentially leading to data theft, malware installation, or system compromise if a user is tricked into opening a malicious spreadsheet.

Technical details

A heap-based buffer overflow exists in Microsoft Office Excel, triggered by improper bounds checking in the application's memory handling. The vulnerability requires local access and likely involves opening a specially-crafted Excel file (.xls, .xlsx, or similar). An attacker can exploit this memory corruption to overwrite heap structures and achieve arbitrary code execution with the privileges of the logged-in user. Microsoft has released patches to address this vulnerability.

Affected products

  • Microsoft Office Excel <UNKNOWN>

Timeline

  • 2026-08-11: disclosed

References

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