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Microsoft Office 0-day Vulnerability CVE-2026-21509 Exploited; Emergency Fix Released

First seen 27 Jan 2026, 13:01 UTC • Pcworld

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Microsoft Office 2016 to 2024 and Office 365 apps are affected by a zero-day vulnerability (CVE-2026-21509) that is currently being exploited in attacks. Microsoft has released emergency security updates to address this issue.

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Microsoft Office 0-day Vulnerability CVE-2026-21509 Exploited; Emergency Fix Released

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