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.

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 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.

Chrome is rolling out an update for its desktop browser. The update includes 26 security fixes, two of which Google rates as critical use-after-free vulnerabilities.

How to update Chrome

If you don’t want to wait for the rollout to reach you, manually updating is easy.

The easiest option is to allow Chrome to update automatically. But you can end up lagging behind if you never close your browser or if something goes wrong with the update.

To update manually, click the More menu (three dots), then go to Settings > About Chrome. If an update is available, Chrome will start downloading it automatically. Restart Chrome to complete the update, and you’ll be protected against these vulnerabilities.

You can find an explanation of the version numbering system and step-by-step instructions in our guide: How to update Chrome on every operating system.

Technical details

Let’s look at the two critical vulnerabilities. Both are use-after-free (UAF) vulnerabilities. A use-after-free vulnerability occurs when a program attempts to access a memory location after it has been freed. That can cause crashes or, in some cases, allow an attacker to run their own code.

The first, tracked as CVE-2026-84353, was found in Shared Tab Groups and could allow a remote attacker using social engineering to execute arbitrary code outside the browser sandbox via a crafted HTML page. Here, social engineering likely means an attacker would have to lure you to a malicious website or open an email in HTML format.

The other critical vulnerability, tracked as CVE-2026-84352, was found in WebGL. WebGL, short for Web Graphics Library, is a browser technology that lets websites display interactive 2D and 3D graphics. The vulnerability could allow a remote attacker to execute arbitrary code outside the sandbox via a crafted HTML page.

Chrome vulnerabilities that enable remote code execution outside the browser sandbox are particularly valuable to attackers because they can turn a visit to a malicious or compromised website into direct code running on the underlying operating system, often without requiring additional exploitation steps.

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