Quick answers
- Is CVE-2026-40360 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-40360 being exploited in the wild.
- How severe is CVE-2026-40360?
- High severity, with a CVSS score of 7.8, published 12 May 2026.
- Which products and versions are affected?
- Microsoft Office Excel.
- Is there a fix for CVE-2026-40360?
- 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-2026-40360 attacked?
- It is attacked with local access, in a network appliance.
- Am I affected by CVE-2026-40360?
- Check whether you run Microsoft 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
An out-of-bounds read vulnerability (CWE-125) exists in Microsoft Office Excel. The flaw is triggered when the application fails to properly validate input while processing a crafted Excel file. An attacker can exploit this by convincing a local user to open a malicious document, allowing the attacker to read sensitive information from the process memory. According to the CVSS vector, while the attack is local and requires user interaction, it can lead to high impacts on confidentiality, integrity, and availability. Microsoft has released information regarding this vulnerability via their Security Update Guide.
Affected products
- Microsoft Office Excel
Timeline
- 2026-05-12: disclosed
- 2026-05-12: advisory: Published by Microsoft and NVD