CVE-2026-55057 Details

A vulnerability allowing information disclosure has been identified in Microsoft Office due to an integer overflow or wraparound. This issue allows an unauthorized attacker to locally disclose information by exploiting the vulnerability. The vulnerability affects multiple Office products, including Microsoft 365 Apps for Enterprise, Office 2019, Office 2016, and various editions of Office LTSC for Mac and Windows.

Users can download the security update for this vulnerability through the Microsoft Update Catalog. For Microsoft 365 Apps for Enterprise, the update is available via Click-to-Run. Instructions for downloading the security update for other affected Office products can be found in the Microsoft Office Update Guide.