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VULNERABILITY BRIEF 🟠 High Advisory

Microsoft releases update to address zero-day vulnerability in Microsoft Office

Microsoft has published three out-of-band (OOB) updates so far in January 2026. One of these updates was released to address a vulnerability, CVE-2026-21509, affecting Microsoft Office that has been reportedly exploited in the wild.

Verisq™ Intelligence · 📅 January 29, 2026 · 📰 blog.talosintelligence.com
🟠
Severity
High
AD
Type
Advisory
📰
Source
blog.talosintelligence.com

Microsoft has published three out-of-band (OOB) updates so far in January 2026. One of these updates was released to address a vulnerability, CVE-2026-21509, affecting Microsoft Office that has been reportedly exploited in the wild.

📰 Original Source
https://blog.talosintelligence.com/microsoft-oob-update-january-2026/ ↗

This Verisq Intelligence Brief is an independent analysis. Read the original reporting at the link above.

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