Patch Tuesday: Update now to fix 421 flaws, including three zero-days
Brief
Microsoft’s August 2026 Patch Tuesday addresses 421 Microsoft vulnerabilities , including 62 rated Critical. One Windows vulnerability has been exploited in the wild by the Lazarus group to gain SYSTEM privileges.
The August update is smaller than July’s record-breaking release, but it’s still among Microsoft’s largest Patch Tuesday batches.
More importantly, it includes several flaws likely to attract attacker interest: a publicly disclosed Windows privilege escalation flaw with a proof-of-concept (PoC), a newly completed unauthenticated SharePoint remote code execution (RCE) chain, and a potentially wormable Windows DNS Server flaw.
How to apply patches and check if you’re protected
These updates fix security problems and help keep your Windows PC protected. Here’s how to make sure you’re up to date:
- Click the Start button, then open Settings .