Microsoft released its November 2026 Patch Tuesday updates on November 10, and it's one of the biggest ever. If you own a Windows PC or laptop, you need to install these updates — one of the flaws is already being exploited by attackers to steal Windows login credentials through Outlook.

What Microsoft Patched This Week

Microsoft patched 1,093 CVEs in its November 2026 Patch Tuesday release, including one Microsoft Outlook zero-day flaw (CVE-2026-124194) that was exploited. Of those, 63 were rated critical, 1,029 rated as important, and one rated as moderate. That's down from October's record of 1,413, but it's still the second-largest Patch Tuesday release to date.

The updates cover Windows 11 and older supported Windows versions, along with Office, Exchange, SharePoint, SQL Server, and Azure services. Microsoft released the November 2026 Patch Tuesday updates for Windows 11 26H2, 25H2 and 24H2, with a separate package for Windows 11 23H2.

The Outlook Zero-Day: Why It Matters for Regular Users

The one flaw that's already being abused by attackers is CVE-2026-124194, a Microsoft Outlook moderate-severity flaw (CVSS 6.5) marked as Exploitation Detected, that can leak a user's NTLMv2 hash when they open a crafted message file.

In plain English: just opening the wrong email or email attachment can hand your Windows login fingerprint to an attacker. The actively exploited Outlook zero-day CVE-2026-124194 enables Windows credential theft and potential NTLM relay attacks. Once attackers have that credential hash, they can potentially impersonate you on other systems on the same network — a serious problem for any small business running a shared file server or domain. If you think your PC has already been compromised by a phishing email, it's worth having a technician check the system for malware and stolen credentials before you log in to banking or work accounts again.

Other High-Risk Fixes Buried in This Release

Beyond the Outlook bug, several wormable flaws are worth knowing about. The release includes Critical RCEs like the zero-click Exchange path CVE-2026-116928 and an LDAP flaw rated 9.8. Exchange Server also received a separate critical fix, CVE-2026-118207, which carries a score of 8.8 and could allow an attacker with low-level access to execute malicious code. Windows Message Queuing received five critical remote code execution fixes, while Hyper-V received eight critical elevation-of-privilege updates. Microsoft also patched critical vulnerabilities involving Windows Schannel, TCP/IP, the Print Spooler and network device discovery services.

Most home users won't have LDAP or Exchange exposed to the internet, but the Schannel, TCP/IP, and Print Spooler fixes affect virtually every Windows PC and laptop in use today.

Install Hiccups to Watch For

As with any large Patch Tuesday, some PCs will stumble on the install. Early reports already point to Windows 11 KB5132061 update download and install failing with a 0x800f0993 error on some machines. If your update loops, rolls back, or leaves your PC stuck at a black screen, don't keep forcing reboots — that's a good way to corrupt the drive and end up needing professional file recovery.

On the plus side, this release also includes some useful fixes beyond security: Microsoft's November 2026 updates for Windows 11 fix USB audio, printer installation, and Remote Desktop problems while strengthening NTLM authentication and PowerShell script verification. If your printer or USB headset stopped working after the October update, this patch may clear it up.

How to Install the Updates Safely

Open Settings → Windows Update → Check for updates, and let the patch download fully before restarting. Plug laptops into the charger first — a half-finished Windows update on a drained battery is one of the most common reasons a PC won't boot afterward, and that kind of failure often ends up on the bench at a local repair shop for a rescue.

What This Means for York, PA

York-area customers who use Outlook for work email should install this update today — the attack that leaks your Windows password is already being used in the wild. If your PC stalls on the update or won't restart afterward, bring it in to York Computer Repair at 2069 Carlisle Rd; we're open Monday–Friday 9–5.

Microsoft's November Patch Tuesday Fixes 1,000+ Windows Flaws — Including an Outlook Zero-Day