Microsoft Patch Tuesday: 6 exploited zero-days fixed in February 2026

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Actively Exploited

Overview

In February 2026, Microsoft addressed over 50 security vulnerabilities during its Patch Tuesday update, including six zero-day flaws that were actively exploited by attackers. Notably, three of these zero-days involve security feature bypasses. One of the vulnerabilities, identified as CVE-2026-21513, impacts the MSHTML/Trident browser engine used in Internet Explorer on Windows, while CVE-2026-21514 affects Microsoft Word. Attackers can exploit these vulnerabilities by tricking users into opening malicious files or links. As these security holes are actively being exploited, users and organizations must apply the updates promptly to protect their systems from potential breaches.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Microsoft Windows (Internet Explorer), Microsoft Word
  • Action Required: Users are advised to install the latest security updates from Microsoft to mitigate these vulnerabilities.
  • Timeline: Newly disclosed

Original Article Summary

Microsoft has plugged 50+ security holes on February 2026 Patch Tuesday, including six zero-day vulnerabilities exploited by attackers in the wild. The “security feature bypass” zero-days Among the zero-days fixed are three vulnerabilities that allow attackers to bypass a security feature. CVE-2026-21513 affects the MSHTML/Trident browser engine for the Microsoft Windows version of Internet Explorer, and CVE-2026-21514 affects Microsoft Word. The former can be exploited by attackers by convincing a user to open a malicious … More → The post Microsoft Patch Tuesday: 6 exploited zero-days fixed in February 2026 appeared first on Help Net Security.

Impact

Microsoft Windows (Internet Explorer), Microsoft Word

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 are advised to install the latest security updates from Microsoft to mitigate these vulnerabilities. Specific patches addressing these issues were released as part of the February 2026 Patch Tuesday.

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 Windows, CVE, Zero-day, and 4 more.

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