Microsoft today issued updates to fix more than 1,400 security vulnerabilities in its Windows operating systems and other software. Today’s epic patch batch dwarfs September’s record of nearly 1,000 fixes, which was already about ten times the normal monthly patch load from Redmond.

Just one of the weaknesses patched this week is considered a “zero day,” or already exploited in the wild. CVE-2026-96951 is a security feature bypass in the Windows Shell that affects Windows 10 and 11 systems, as well as some Server versions.

Windows 10 users might be wondering if they can still expect security updates after this month. Microsoft had been slated to stop shipping updates for Windows 10 systems in October 2025, but ended up adding another year of free updates after considerable pushback. A few months ago, Microsoft quietly extended that support for another year (until October 2027).

At least 78 of the flaws fixed this month are rated “critical,” meaning they could be exploited with little or no action by the user, and most of those critical bugs allow an attacker to execute code of their choice on the vulnerable system.

While Microsoft said there are no signs anyone is exploiting it yet, a security feature bypass in the .NET Framework (CVE-2026-108398) was publicly disclosed prior to today, potentially giving attackers advance time to work out how to exploit the bug.

Satnam Narang at Tenable said the number of flaws fixed this month far surpasses the previous record-setting year 2020, when Microsoft patched 1,261 CVEs.

“We’ve now crossed the 4,000 CVE mark with two months left to go,” he said.

Microsoft credits large language models for the high volume of bug discovery, and presumably AI gets credit for many of the patches used to fix these flaw. Meanwhile, security experts have been warning that these unusually large patch volleys from Microsoft are placing extra strain on corporate security teams, which often have to test individual updates before deploying them across a network to ensure the fixes don’t cause problems for other software.

Tyler Reguly, associate director of security research and development at Fortra, notes that just 26 Microsoft vulnerabilities appeared in the “Known Exploited Vulnerabilities” (KEV) catalog maintained by the U.S. Cybersecurity & Infrastructure Security Agency (CISA) so far this year, and security teams would do well to prioritize patching those 26 vulnerabilities first.

“Security leaders should focus on exploitable risk, and ask whether their teams have the clarity, capacity and support to act,” Reguly said.

Which vulnerabilities deserve the most scrutiny in your organization? The folks at Cisco Talos have a useful roundup of the more noteworthy flaws that Microsoft fixed today, and of course the SANS Internet Storm Center has a reliable roundup that indexes vulnerabilities by severity, CVE number and affected software.

Microsoft Corp. today issued updates to plug at least 974 security holes in its Windows operating systems and other software, by far its biggest single patch batch ever. Microsoft says artificial intelligence is helping to speed the discovery of vulnerabilities, but security experts warn that many organizations already are struggling to prioritize the more human-intensive endeavor of testing and deploying so many fixes each month.

Image: Shutterstock.com, Kirill Makarov.

This month’s patch bundle obliterates the software giant’s previous record set in July, when it released updates for at least 570 security vulnerabilities. September’s Patch Tuesday brings this year’s total to more than 2,600, more than twice Microsoft’s previous record-setting patch year in 2020 (1,245) and with three more months to go.

There are two “zero-day” flaws fixed this month that are being actively exploited: both CVE-2026-81963 and CVE-2026-85880 allow an attacker to elevate their privileges on Windows system.

Fully 113 of the bugs addressed today earned Microsoft’s “critical” rating, meaning they could be abused by malware or miscreants to seize control over a vulnerable Windows machine with little or no help from the user.

Among the more serious critical flaws this month is CVE-2026-69730, a DNS weakness present in Windows Server 2012 onward and on Windows 10. Microsoft warns that an unauthenticated attacker could leverage this weakness simply by sending a specially crafted packet to an affected system, and that it is likely to be exploited.

Also scary is CVE-2026-69829, a critical, remote code execution flaw in the Windows Shell. This vulnerability has a CVSS base score of 9.8 (10 is the most severe), and can be exploited with low attack complexity, no privileges, and no user interaction.

Microsoft’s summary of the security updates released today. Image: msrc.microsoft.com.

Microsoft is hardly alone in shipping monster patch bundles lately. Many other large software companies, including Adobe, Cisco, Google, Mozilla and Oracle, all have recently credited AI-assisted research with increasing their patch cadence and volume (Google said today it is now going to ship security updates every two weeks).

Tyler Reguly, associate director of security research and development at Fortra, said one core challenge with deploying Windows updates is that they need to be tested before being installed across an organization because not all third-party software works seamlessly in the face of changes to the underlying operating system.

“It’s time to put our CISOs and CSOs on notice,” Reguly said. “How are you helping your teams through these difficult times? Do you have your teams deploy after hours and on weekends to avoid disruption to the business environment? Do you reward them for that effort? Time to dig into your budget and buy dinner for your teams that are working on Saturday to get patches rolled out before users return to work on Monday.”

Satnam Narang is senior staff research engineer at Tenable. Narang said it’s important to recognize that while the number of vulnerabilities being patched by Microsoft is rising, the number of flaws that can and will affect most organizations remains quite low.

“AI-assisted vulnerability discovery in 2026 is creating larger haystacks, but it isn’t finding more needles,” he said. “It’s critical that organizations understand which vulnerabilities actually apply to them, whether they pose a threat by being reachable and exploitable, and prioritize remediation based on this risk context.”

Of course, regular Windows users don’t need to test patches before deploying them, but they still need to open Windows Update periodically or else assent to the program’s nag notices about pending updates. And at the rate these Windows patch releases are ballooning in size, it’s probably best not to let them pile up month after month.

Enterprise Windows admins will want to keep an eye on askwoody.com for news of any updates that appear to be causing problems. As always, the SANS Internet Storm Center has a per-patch breakdown ordered by severity and urgency.