Junglewise Threat Intelligence

CVE-2026-56193: Microsoft Office out-of-bounds read information disclosure

CVE-2026-56193 · Severity: high · CVSS 7.1 · Published 2026-07-14

Technologies: Microsoft Office LTSC 2024, Microsoft Office LTSC for Mac 2024, Microsoft Office 365 for Mac, Microsoft Office LTSC for Mac 2021, Microsoft Office LTSC 2021, Microsoft Office 2016, Microsoft 365 Apps for Enterprise, Microsoft Office 2019. Vendors: Microsoft.

Executive brief

A security vulnerability exists in several versions of Microsoft Office 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. This could lead to the unauthorized disclosure of private data or cause the application to crash, impacting both data confidentiality and system stability.

Technical details

An out-of-bounds read vulnerability (CWE-125) exists in Microsoft Office across multiple versions, including Office 2016, 2019, LTSC 2021/2024, and Microsoft 365 Apps. The flaw is triggered when the application processes a specially crafted file, leading to memory access outside of intended buffers. An attacker can exploit this locally by convincing a user to open a malicious document (User Interaction required). Successful exploitation can result in the disclosure of sensitive information from the process memory or a denial-of-service condition. Microsoft has released security updates to address this issue.

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 Office LTSC for Mac 2021 < 16.111.26071215
  • Microsoft Office LTSC for Mac 2024 < 16.111.26071215

Timeline

  • 2026-07-14: disclosed: Initial disclosure by Microsoft
  • 2026-07-14: advisory: NVD record published

References

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