CVE-2026-21259
Microsoft Excel Elevation of Privilege Vulnerability
CVSS Score
7.8
EPSS Score
0.0%
EPSS Percentile
8th
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to elevate privileges locally.
| Vendor | microsoft |
| Product | microsoft 365 apps for enterprise |
| Ecosystems | |
| Industries | TechnologyEnterprise |
| Published | Feb 10, 2026 |
| Last Updated | Apr 10, 2026 |
Stay Ahead of the Next One
Get instant alerts for microsoft microsoft 365 apps for enterprise
Be the first to know when new high vulnerabilities affecting microsoft microsoft 365 apps for enterprise are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Affected Versions
Microsoft / Microsoft 365 Apps for Enterprise
16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft / Microsoft Excel 2016
16.0.0.0 < 16.0.5539.1002
Microsoft / Microsoft Office 2019
19.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft / Microsoft Office LTSC 2021
16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft / Microsoft Office LTSC 2024
16.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft / Office Online Server
16.0.0.0 < 16.0.10417.20097