CVE-2026-120785: Microsoft Office Excel heap-based buffer overflow

CVE-2026-120785 · Severity: high · CVSS 8.8 · Published 2026-11-10

Microsoft Office Excel contains a heap-based buffer overflow vulnerability that allows an attacker to execute arbitrary code on a user's computer over a network. This could lead to complete system compromise, data theft, or installation of malware. Users of Excel are at risk when opening specially crafted spreadsheet files.

Technologies: Microsoft Office Excel. Vendors: Microsoft.

Quick answers

Is CVE-2026-120785 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-120785 being exploited in the wild.
How severe is CVE-2026-120785?
High severity, with a CVSS score of 8.8, published 10 November 2026.
Which products and versions are affected?
Microsoft Office Excel.
Is there a fix for CVE-2026-120785?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-120785 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-120785?
Check whether you run Microsoft Office Excel. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A heap-based buffer overflow in Microsoft Office Excel allows remote code execution when a user opens a maliciously crafted spreadsheet file. The vulnerability is exploitable over a network with user interaction (file opening). Successful exploitation grants an attacker the same privileges as the user running Excel.

Affected products

  • Microsoft Office Excel

Timeline

  • 2026-11-10: disclosed

References

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