【Vulnerability Alert】High-Risk Security Vulnerability in Microsoft Excel (CVE-2026-62870); Please Confirm and Patch Promptly

• Subject: 【Vulnerability Alert】High-Risk Security Vulnerability in Microsoft Excel (CVE-2026-62870); Please Confirm and Patch Promptly

• Description:
  • Forwarded Security Alert from National Information Sharing and Analysis Center (NISAC) NISAC-200-202608-00000002
  • Researchers have discovered a Use After Free vulnerability (CVE-2026-62870) in Microsoft Excel. An unauthenticated remote attacker can exploit this vulnerability to execute arbitrary code. Please confirm and apply patches as soon as possible.
• Affected Platforms:
  • Microsoft 365 Apps for Enterprise for 32-bit Systems
  • Microsoft 365 Apps for Enterprise for 64-bit Systems
  • Microsoft Excel 2016 (32-bit edition) versions prior to 16.0.5561.1001
  • Microsoft Excel 2016 (64-bit edition) versions prior to 16.0.5561.1001
  • Microsoft Office 2019 for 32-bit editions
  • Microsoft Office 2019 for 64-bit editions
  • Microsoft Office LTSC 2021 for 32-bit editions
  • Microsoft Office LTSC 2021 for 64-bit editions
  • Microsoft Office LTSC 2024 for 32-bit editions
  • Microsoft Office LTSC 2024 for 64-bit editions
• Recommendations:
  • The vendor has released security patches for this vulnerability. Please refer to the official advisory to perform updates: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62870
• Reference Information:
  1. https://nvd.nist.gov/vuln/detail/CVE-2026-62870
  2. https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62870

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