5.5Medium
Microsoft 365 Apps
CVE-2026-85875
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
What this means for your business
- It affects Microsoft 365 Apps. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it only with access to the machine itself, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 31% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Microsoft 365 Apps, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 5.5 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N- Weakness
- CWE-125
- Assigned by
- secure@microsoft.com
Dates
- Published
- 2026-09-08
- Last modified
- 2026-09-17
- Sources
- NVD
Affected products
- Microsoft 365 Appsall versions
- Microsoft Excel2016
- Microsoft Microsoft 365all versions
- Microsoft Office 2016all versions
- Microsoft Office 2019all versions
- Microsoft Office 2021all versions
- Microsoft Office 2024all versions
As listed in the NVD configuration data. Not a statement about your estate.