Microsoft Patches Record 622 Vulnerabilities Using AI Tools

Microsoft Corporation released a record-breaking Patch Tuesday update in July 2026, addressing between 570 and 622 vulnerabilities across Windows operating systems and other software. The volume of fixes, which included 428 Chromium bugs and 58 critical-severity flaws, was driven by the adoption of AI-powered scanning tools. These include the company's own MDASH system, Anthropic's Claude Mythos model via Project Glasswing, and OpenAI's models through the Trusted Access for Cyber initiative.

The update patched three zero-day vulnerabilities, two of which were actively exploited in the wild: CVE-2026-56155 affecting Active Directory Federation Services and CVE-2026-56164 affecting Microsoft Office SharePoint. A third zero-day targeting BitLocker encryption was also disclosed. Both the SharePoint and Active Directory flaws are elevation of privilege vulnerabilities that could grant attackers administrator control.

Microsoft stated that the increased patch frequency is a response to bad actors using AI to find flaws. While updates are available for Windows 10 and 11, the company temporarily halted the rollout for some Dell computers with Intel processors due to incompatibility issues causing battery drain and system shutdowns. Other software vendors, including Google, Oracle, and Cisco, are reportedly increasing their patch cadence as AI-driven discovery becomes an industry standard.