Microsoft Patches Office Zero-Day Likely Exploited in Targeted Attacks

SecurityWeek
Actively Exploited

Overview

Microsoft has released a patch for a zero-day vulnerability in its Office software, identified as CVE-2026-21509. This flaw allows attackers to bypass certain security features, potentially putting users at risk. Reports suggest that the vulnerability may have already been exploited in targeted attacks against specific organizations. As a result, it's crucial for all users of Microsoft Office to apply this patch promptly to protect themselves from potential intrusions. The patch is part of Microsoft's ongoing efforts to enhance the security of its products and safeguard user data from malicious activities.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Microsoft Office products, including various versions of Office applications.
  • Action Required: Users should immediately apply the latest security updates provided by Microsoft to address CVE-2026-21509.
  • Timeline: Newly disclosed

Original Article Summary

The vulnerability is tracked as CVE-2026-21509 and it can be exploited to bypass security features. The post Microsoft Patches Office Zero-Day Likely Exploited in Targeted Attacks appeared first on SecurityWeek.

Impact

Microsoft Office products, including various versions of Office applications.

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Users should immediately apply the latest security updates provided by Microsoft to address CVE-2026-21509. Specific patch numbers or versions were not mentioned, but users can check for updates through the Microsoft Update service or the official Microsoft website.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Zero-day, Microsoft, and 2 more.

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