#VU122585 Out-of-bounds read in Microsoft products - CVE-2026-21261
Published: February 10, 2026
Vulnerability identifier: #VU122585
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-21261
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Office Online Server
Microsoft Office
Microsoft Excel
Microsoft 365 Apps for Enterprise
Microsoft Office LTSC
Office Online Server
Microsoft Office
Microsoft Excel
Microsoft 365 Apps for Enterprise
Microsoft Office LTSC
Software vendor:
Microsoft
Microsoft
Description
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to a boundary condition in Microsoft Excel. A remote attacker can create a specially crafted Office file, trick the victim into opening it, trigger an out-of-bounds read error and read contents of memory on the system.
Remediation
Install updates from vendor's website.