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Microsoft Windows 11 mandatory Patch Tuesday updates (KB5089549, KB5087420)

Security Patch Release
First reported
Last updated
Happening score
H score 26
1 unique sources, 1 articles

Summary

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Microsoft released mandatory Windows 11 cumulative updates for KB5089549 and KB5087420, delivering the May 2026 Patch Tuesday fixes for 120 vulnerabilities across 25H2/24H2 and 23H2. The release is a broad security patch bundle rather than a single-CVE fix, and it also includes bug fixes and feature changes. Systems on the affected Windows 11 versions should treat the update as a high-priority security deployment.

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Timeline

  1. 12.05.2026 21:09 2 articles · 1mo ago

    Microsoft releases Windows 11 KB5089549 and KB5087420

    Initial Disclosure

    On May 12, 2026, Microsoft released mandatory Windows 11 cumulative updates KB5089549 and KB5087420 for 25H2/24H2 and 23H2, bundling the May 2026 Patch Tuesday fixes for 120 vulnerabilities and delivering the same fixes across the supported Windows 11 versions.

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