May 2026 Patch Tuesday: no zero-days but plenty to fix

This month’s Patch Tuesday remedies 137 security vulnerabilities, including 31 marked critical by Microsoft, with no zero-days actively exploited in the wild. Microsoft defines a zero-day as “a flaw in software for which no official patch or security update is available yet.” This month, Microsoft has not observed any included vulnerability being exploited in production environments. Still, this release is far from low-risk.