August 2026 Windows Update — 400 Fixes and a Zero-Day Linked to North Korea

Microsoft shipped around 400 security fixes yesterday. Forty-two of them are Critical. One zero-day is already being used in real attacks, attributed to North Korea's Lazarus Group. Install it today.

The zero-day that matters

One of the three is being used in the wild right now. The other two were publicly disclosed but haven't been spotted in actual attacks yet.

Other flaws worth knowing about

• CVE-2026-68794, CVE-2026-68804, CVE-2026-68816, Microsoft Excel. Three separate Critical remote code execution flaws. Open a malicious spreadsheet, game over.
• CVE-2026-64907, CVE-2026-63518, CVE-2026-63525, Microsoft Word. Same story, different app. Malicious documents that run code when opened.
• CVE-2026-62824, Remote Desktop Client. Critical RCE. If you connect to a dodgy RDP server, it can run code on your machine.
• CVE-2026-62822, Windows GDI+. Critical RCE in the graphics rendering layer. Could be triggered by a crafted image file.

The sheer number of Office vulnerabilities this month is hard to ignore. If you use Word or Excel regularly (and who doesn't), this update matters.

How to install

1. Settings, then Windows Update
2. Check for updates
3. Wait 10-30 minutes
4. Restart when prompted, not two days later

Hotpatching is now a thing

August is one of the first months where Windows 11 supports hotpatching, which means the security fix can apply without a restart on supported configurations. Most home PCs won't see this yet (it's rolling out through Windows Autopatch first), but it's coming. The days of forced restarts for every security update might actually be numbered.

Windows 10 (if you're still there)

This month's Windows 10 patch is KB5120249. You only get it if you're enrolled in the free Extended Security Updates programme. That runs out in October 2026, so if you haven't started thinking about upgrading, now is the time. See the Windows 10 end-of-life guide for your options.

24H2 Home and Pro: end of support is close

Windows 11 version 24H2 Home and Pro editions reach end of support on 13 October 2026. That's two months away. If you're on 24H2, you'll want to move to 25H2 before then. Windows Update should offer it automatically, but if it hasn't, go check.

If Windows Update itself is broken

A PC that can't update can't protect itself. The usual culprits are low disk space, corrupted update files, or another antivirus clashing with Defender. I've covered the fixes in my common PC problems post. If storage is the bottleneck, speeding up a slow Windows 11 PC has that covered too. And if nothing is working and you're stuck, that's what I'm here for.

For the full technical breakdown, Bleeping Computer covers every CVE and Krebs on Security covers which ones matter most.

Mark

Mark has been fixing computers since the late '90s and went self-employed in 2008. Based in St Helens since 2013, he works evenings and weekends from his home in Laffak — friendly, affordable repairs for PCs, laptops, and Macs. See reviews on Google