CVE-2026-55134

Published: Jul 14, 2026Modified: Jul 16, 2026

7.8

Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Exploitability: 1.8 / Impact: 5.9

Source: secure@microsoft.com (Secondary)

Description

Stack-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.

Affected (16)

Products: Microsoft: 365 Apps, Microsoft 365, Office 2019, Office 2021, Office 2024, Sharepoint Server, Word

7 products

Sharepoint Server

Configuration A

16 vulnerable

Vulnerable Software	Affected Versions
Microsoft 365 Apps	All versions
Microsoft 365 Apps	All versions
Microsoft Microsoft 365	All versions
Microsoft Office 2019	All versions
Microsoft Office 2019	All versions
Microsoft Office 2021	All versions
Microsoft Office 2021	All versions
Microsoft Office 2021	All versions
Microsoft Office 2024	All versions
Microsoft Office 2024	All versions
Microsoft Office 2024	All versions
Microsoft Sharepoint Server	Before 16.0.19725.20434
Microsoft Sharepoint Server	Version 2016
Microsoft Sharepoint Server	Version 2019
Microsoft Word	Version 2016
Microsoft Word	Version 2016

Related CWEs

Stack-based Buffer Overflow

A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55134

Source: secure@microsoft.com

PatchVendor Advisory

Timeline

No history available yet.