Executive brief
A security vulnerability exists in Microsoft Office and SharePoint that could allow an attacker to access sensitive information on a user's computer. To exploit this, an attacker would typically need to trick a user into opening a specially crafted file. Successful exploitation could lead to the unauthorized disclosure of private data stored in the system's memory.
Technical details
An out-of-bounds read vulnerability (CWE-125) exists in multiple Microsoft Office products and SharePoint Server. The flaw is triggered when the application improperly handles memory while parsing a specially crafted file. An attacker can exploit this by convincing a user to open a malicious document, allowing the attacker to read data from memory locations outside of the intended buffer. This can lead to the disclosure of sensitive information that could be used to facilitate further attacks. Microsoft has released security updates to address this issue across affected versions of Office 2016, 2019, LTSC, and Microsoft 365 Apps.
Affected products
- Microsoft Office 2016 < 16.0.5561.1000
- Microsoft Office 2019 All versions
- Microsoft Office LTSC 2021 All versions
- Microsoft Office LTSC 2024 All versions
- Microsoft 365 Apps for Enterprise All versions
- Microsoft Office 365 for Mac < 16.111.26071215
- Microsoft SharePoint Enterprise Server 2016 < 16.0.5561.1001
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory