Numeric Truncation Error in Microsoft products - CVE-2026-55142
Published: July 17, 2026
Vulnerability identifier: #VU138236
CSH Severity: Medium
CVSS v4: 6.7 [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]
CVE-ID: CVE-2026-55142
CWE-ID: CWE-197
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to numeric truncation error in Microsoft Office Word when parsing a crafted Office file. A remote attacker can send a specially crafted file and convince the victim to open it to disclose sensitive information.
The disclosed information may include portions of heap memory. The Preview Pane is not an attack vector.
Affected software
Microsoft Office for macOS
Microsoft Word
Microsoft SharePoint Server
Microsoft Word
Microsoft SharePoint Server
How to mitigate CVE-2026-55142
Install security update from vendor's website.
Microsoft Office for macOS - update to 16.111.26071215
Microsoft Word - update to 16.0.5561.1000
Microsoft SharePoint Server - addressed in versions 16.0.5561.1001, 16.0.10417.20175, 16.0.19725.20434
Microsoft Word - update to 16.0.5561.1000
Microsoft SharePoint Server - addressed in versions 16.0.5561.1001, 16.0.10417.20175, 16.0.19725.20434