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CVE-2026-55054ImportantMonitor

Microsoft Excel Information Disclosure Vulnerability

Severity Important  ·  Urgency Monitor

Why it matters: Important severity (CVSS 6.5)

Information Disclosure · Important · CVSS 6.5. Affects: Office Online Server, Microsoft Office, Microsoft 365 Apps, Microsoft Office LTSC for Mac, Microsoft Office LTSC, Microsoft Excel.

CVSS 6.5EPSS 0.6%Security update published 2026-08-21Applies to Cloud + on-premisesKB5002884NVD

Affected: Office Online Server, Microsoft Office, Microsoft 365 Apps, Microsoft Office LTSC for Mac, Microsoft Office LTSC, Microsoft Excel

Related changes

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