Quick answers
- Is CVE-2026-65807 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-65807 being exploited in the wild.
- How severe is CVE-2026-65807?
- High severity, with a CVSS score of 8.8, published 11 August 2026.
- Which products and versions are affected?
- Microsoft Office Excel.
- Is there a fix for CVE-2026-65807?
- 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-2026-65807 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-65807?
- 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 type confusion vulnerability exists in Microsoft Office Excel's resource handling, where the application incorrectly validates or processes objects of incompatible types during parsing or execution. This vulnerability can be triggered by a specially crafted Excel file delivered over the network. The attack requires user interaction (opening the malicious file) but no authentication. Successful exploitation allows arbitrary code execution with the privileges of the user running Excel, potentially leading to complete system compromise. A patch is expected to be available through Microsoft's security updates.
Affected products
- Microsoft Office Excel
Timeline
- 2026-08-11: disclosed