.NET Denial of Service Vulnerability
CVE-2026-120796
Summary
Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code locally.
Products covered
Microsoft 365 Apps for Enterprise for 32-bit Systems
Microsoft 365 Apps for Enterprise for 64-bit Systems
Microsoft Office LTSC 2021 for 32-bit editions
Microsoft Office LTSC 2021 for 64-bit editions
Microsoft Office LTSC 2024 for 32-bit editions
Microsoft Office LTSC 2024 for 64-bit editions
Remediation
Click to Run
Vendor-listed fixes
https://aka.ms/OfficeSecurityReleases
CVEs in this advisory 1
Update history
What changed in later vendor updates
SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.
- The vendor changed the advisory summary.
- CVSS changed from 8.8 to 7.8.
- The vendor changed the advisory's last-updated date.
Updates
- Published by Microsoft Security Response Center
The publication date reported by the vendor.
- Added to SecurityAlert
We collected the advisory from the official source.
- Updated by Microsoft Security Response Center
The vendor changed the advisory after it was first published.
- Confirmed at the source
Our collector saw this advisory during a later source check.