Microsoft defends Windows 11 security, citing AI-driven patch surge

On November 5, 2026, Microsoft addressed concerns about Windows 11 security in an official blog post. Nuno Costa, Director of Windows Service and Delivery Partnerships, stated that system security had "not deteriorated because of AI."

Microsoft published month-by-month figures for patches limited to Windows systems across 2025 and 2026. In 2025, the monthly totals were: 1,329 in January, 373 in February, 374 in March, 90 in April, 446 in May, 441 in June, 103 in July, 672 in August, 587 in September, and 134 in October. In 2026, they were: 93 in January, 32 in February, 483 in March, 131 in April, 666 in May, 1,207 in June, 4,133 in July, 2,333 in August, 7,226 in September, and 1,123 in October. The year-over-year changes were a 29.5% decline in January, a 13.5% decline in February, a 29.7% rise in March, a 45.6% rise in April, a 50.0% rise in May, a 172.7% rise in June, a 301.0% rise in July, a 247.8% rise in August, a 1,151.7% rise in September, and a 738.1% rise in October.

Microsoft explained that during the October 2026 Patch Tuesday, it fixed a total of 1,413 CVE vulnerabilities, of which more than 1,100 were Windows-related, compared with just 134 in the same period last year. The sharp rise in patch counts, according to Microsoft, does not indicate a worsening security environment; rather, it reflects the company using AI to scan code more deeply and at greater scale, enabling it to discover and fix more vulnerabilities. As of now, the matter stands at the point of Microsoft having published this explanation in its blog post.