A cybersecurity illustration shows an email attachment protected by a shield, blocking a hacker’s server and syncing Office and Windows.
Microsoft shipped another four-digit security release for November's Patch Tuesday. The number to act on first, though, is one. Only one flaw in the November 10 batch is confirmed as exploited, and it sits in classic Outlook. Windows Update doesn't install its fix. You get it through Office's own update channel, so a lot of machines may stay exposed even after Windows shows as fully patched.

A cybersecurity illustration shows an email attachment protected by a shield, blocking a hacker’s server and syncing Office and Windows. Which total is right: 1,092, 1,093 or 1,094?​

Sources disagree on the size of this month's release, so here is each count and where it comes from:

  • IT Brief (UK, Asia and Australia editions) says Microsoft published 1,092 vulnerabilities. The same story quotes Rapid7's Adam Barnett as saying the release includes 1,102 Windows vulnerabilities. That's more than the headline total, so at least one of those figures needs a footnote.
  • KrebsOnSecurity counts 1,093 fixes, with 63 rated critical and 535 privilege-escalation bugs. Krebs says nearly half of the critical flaws are remote code execution issues.
  • The Register puts the count at 1,094, noting it is the second month of more than 1,000 CVEs (October had 1,474).
  • Splashtop also counts 1,094 and adds that Microsoft is also republishing 165 non-Microsoft CVEs. Another tracker lists 1,094 Microsoft CVEs excl. Edge & Azure Linux, with 64 critical.

The likely explanation is methodology. Some trackers include Edge, Azure Linux and republished third-party CVEs, and others leave them out. None of the sources fully reconciles the numbers, so treat "about 1,100" as the honest figure. Krebs adds that Microsoft has now shipped more than 5,100 security patches in 2026. He contrasts that with roughly 100 a month a year ago, and says Microsoft credits AI-assisted bug hunting for the jump.

Section summary: the headline total varies by roughly two to three CVEs depending on what each tracker counts. All of them agree on one exploited zero-day and no publicly disclosed flaws.

CVE-2026-124194: the Outlook bug attackers are already using​

Here is how the flaw works, according to Barnett at Rapid7. Opening a specially crafted malicious file makes classic Outlook connect silently to a location the attacker controls, and that leaks the user's NTLMv2 hash. Barnett says it affects all supported versions of classic Outlook. Krebs reports that Microsoft's advisory lists Microsoft 365 Apps for Enterprise and editions of Microsoft Office.

Dustin Childs of the Zero Day Initiative described the attack to The Register: "Outlook then connects to an attacker-controlled network location without showing the usual external-content warning, which discloses the user's NTLMv2 hash. The attacker can use that hash to authenticate as the user." Microsoft's formal description says the "product UI does not warn user of unsafe actions in Microsoft Office Outlook," and the weakness maps to CWE-356.

Why prioritize a bug with a CVSS score of 6.5 and a "Moderate" rating?

  • Exploitation is confirmed. CISA added CVE-2026-124194 to its Known Exploited Vulnerabilities catalog on November 10, 2026, with a remediation due date of November 24, 2026 for federal agencies.
  • A leaked hash is useful to attackers. Barnett notes it can be used to impersonate the user against another service or cracked offline.
  • Severity ratings don't reflect exploitation. Splashtop points out that for the third month in a row, the vulnerability attackers are actually using is rated below Critical, which is why exploit status should set the order of work.

There is one limiting factor. Barnett says the Preview Pane is not an attack vector, so the user has to actually open the file. That gives some protection, but not much. Getting people to open things is what phishing is for.

The Register notes that Microsoft didn't say when the attacks started, who is battering this bug, and what they are doing with the access post exploitation. Don't read anything into the silence. It isn't evidence of a narrow campaign or of a broad one.

How to patch it: the fix comes through Office, not Windows Update​

This is the step most likely to go wrong. Splashtop says the fix ships in the Microsoft 365 Apps and Office LTSC 2021 and 2024 security updates. TheTechHacker puts it more bluntly: the fix doesn't come through Windows Update at all, it comes through Office's own updater, which a lot of people never look at.

On a single PC:

  • Open Outlook (or Word).
  • Go to File > Account > Update Options > Update Now.
  • Let the update finish, then restart Office apps when prompted.
  • Run Windows Update separately for the OS fixes listed below.

For administrators:

  • List every device running classic Outlook, including Microsoft 365 Apps and Office LTSC installs.
  • Push the November Office security update through your usual channel, whether that's Intune, Configuration Manager or something else.
  • Check that devices actually reached the patched build. Don't assume Click-to-Run handled it on its own.
  • Several trackers suggest a 72-hour target for this one, which is well ahead of CISA's November 24 federal deadline.
  • For threat hunting, Rescana suggests that unexpected Outlook connections to unknown locations, or NTLM events after a user opens a message file, may be leads for CVE-2026-124194, not confirmed signatures.

Users should also hear the usual warning about unexpected message-file attachments. That's an extra layer, not a substitute for patching.

The Windows flaws that deserve attention next​

Rapid7 flagged two Windows bugs that could cause trouble even though neither is exploited yet:

  • CVE-2026-119952 (Schannel): a pre-authentication remote code execution flaw in Windows' TLS implementation, triggered by specially crafted packets. Microsoft's advisory says specific conditions are required for exploitation. Barnett points out that Microsoft still rates exploitation "more likely," and that an attacker may often not need a foothold on the same subnet. Because Schannel runs on so many endpoints, the exposure could be wide.
  • CVE-2026-116928 (Exchange plus Windows Search): pre-auth RCE on an Exchange server through a malicious attachment that Windows Search indexes automatically on Exchange's behalf. The fix is in Windows, not Exchange, so patching Exchange alone won't cover you. Barnett also reminds admins that only Exchange Subscription Edition is still supported.

Rescana's advisory adds an LDAP RCE, CVE-2026-119958, to that list. It says Microsoft marks all three as not exploited and not publicly disclosed.

Section summary: patch Outlook first, then move fast on Windows servers. Exchange hosts and machines with heavy TLS exposure come first.

Lifecycle changes and what else shipped this week​

According to Barnett, .NET 8 LTS, PowerShell 7.4 LTS and Windows 11 Enterprise, Education and IoT editions have moved past their end dates. If you still run any of them, they don't appear in this month's patch reports and won't get fixes from here on.

Other vendors also patched this week. Krebs reports:

  • Chrome 157.0.8103.50 fixes CVE-2026-125350, Chrome's sixth zero-day of the year. It affects Chromium-based browsers, including Edge, so check your Edge version too.
  • Firefox 160 fixes almost 100 CVEs.
  • Adobe patched at least 110 vulnerabilities.
  • Apple shipped out-of-band iMessage fixes.

Analysis: is more patching making anyone safer?​

Barnett questions the volume himself. In his view, every code change that removes a known flaw could introduce new ones for researchers or attackers to find later. The other side of the argument comes from Ivanti's Chris Goettl, quoted by Krebs. About 95,000 CVEs have been assigned across all vendors this year, but only 217 have reached CISA's KEV list. His conclusion is that teams should focus hard on the small set of flaws attackers are actually using.

For November, that means getting the Office update onto every device running Outlook, then working through the Windows server patches. The other thousand-odd fixes can go out on the normal schedule. Back up first, as always.

Update: Additional details (November 11, 2026)​

The new report lists November Windows 11 updates as KB5132061 for versions 26H2, 25H2 and 24H2; KB5132043 for hotpatch devices on those versions; KB5132059 for 26H1; and KB5131087 for 23H2.

CyberInsider counts 726 Windows CVEs in the broader release, while PDQ counts 201 Office CVEs.

 

References

  1. How to Patch CVE-2026-124194 in Outlook and Update Windows 11 express.co.uk
  2. November 2026 Patch Tuesday: Outlook Zero-Day and KB5132061 thetechhacker.com
  3. Microsoft patches 1,092 flaws as Outlook bug was hit - IT Brief UK IT Brief UK 2026-11-11T03:00:16+00:00
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Microsoft's November 2026 Patch Tuesday is out, and the Daily Express headline treats every Windows 11 laptop owner as an emergency. The release really is huge, and one flaw really is being exploited. The detail that matters most for home users got lost, though: the one bug attackers are already using is in Outlook, and its fix doesn't come through Windows Update. If you only check Windows Update, you can fully patch Windows 11 and still have a vulnerable Outlook.
Here's what happened, what the numbers mean, and what to do on a Windows 11 PC.

A laptop displays an email warning alongside software updates and security graphics in a cozy autumn setting. The headline numbers, and why sources disagree​

Microsoft released the November security updates on November 10, 2026 (US time). Its Security Response Center notice tells customers using affected products to install them as soon as possible. The notice also points out that most Microsoft products install security updates automatically by default, with some exceptions.
The size of the release depends on who's counting:
  • The Express says the update fixes 1,094 issues, with 63 rated Critical and one zero-day.
  • Tenable counts 1,093 CVEs, with 63 rated critical, 1,029 rated important, and one rated moderate. PDQ's recap gives the same 1,093 breakdown.
  • Splashtop, CyberInsider and NTCompatible use 1,094.
A one-CVE gap isn't a scandal. Splashtop's write-up hints at why the totals vary: Microsoft is also republishing 165 non-Microsoft CVEs, and trackers count those republished entries differently. The safe summary is "roughly 1,093–1,094 CVEs, 63 Critical, one exploited."
The Express also calls these "1,094 issues with this popular operating system." That's wrong. The count covers Microsoft's whole product range. CyberInsider reports the broader release addresses 1,094 CVEs across Microsoft's products, including 726 under Windows. Microsoft's own notice lists updates for Office, SharePoint, Exchange, SQL Server, Dynamics 365, Azure, .NET and Visual Studio as well as Windows. PDQ notes that Office accounts for 201 of the CVEs.
There's also a typo in the Express piece that needs correcting. It says these are updates that "should be ignored." They aren't. Install them.
Summary: about 1,093–1,094 CVEs across all Microsoft products, of which about 726 are in Windows. 63 are Critical and one is actively exploited.

The zero-day: CVE-2026-124194 in Outlook​

Microsoft's November notice names one vulnerability as exploited before the patch shipped: CVE-2026-124194, a Microsoft Outlook spoofing vulnerability.
Microsoft describes the attack this way, as quoted by the Express:
  • An unauthenticated attacker sends a specially crafted message file.
  • The attacker has to convince the target to open it in an affected version of Outlook.
  • Outlook may then connect to an attacker-controlled network location without displaying its usual external-content warning.
  • That connection can leak authentication information that could be used to impersonate the user. The attack needs network connectivity and the user's interaction.
Several security firms say what that authentication information is. Splashtop says the flaw can leak a user's NTLMv2 hash when they open a crafted message file. It adds that an attacker can use that hash to impersonate the user in follow-on attacks.

Why "spoofing" is a confusing label​

You might expect "spoofing" to mean a faked sender address. It doesn't here. One analysis puts it this way: Microsoft calls it spoofing because the stolen hash lets the attacker impersonate the victim, not because any email sender is forged. The underlying weakness is that the "product UI does not warn user of unsafe actions in Microsoft Office Outlook," which "allows an unauthorized attacker to perform spoofing over a network." The weakness maps to CWE-356.

Why a "Moderate" bug comes first​

The exploited flaw has the lowest severity label in the release. CVE-2026-124194 is rated only Moderate, with a CVSS score of 6.5. Three Outlook bugs in the same release are rated Critical, and none of them is under attack. Splashtop notes that for the third month in a row, the vulnerability attackers are actually using is rated below Critical, which is why exploit status should set the order of work.
Patching teams have learned this the hard way: a severity rating describes what a bug could do, while "Exploitation Detected" tells you attackers are already using it. A stolen NTLM hash is especially damaging in a corporate network. Jack Bicer, Director of Vulnerability Research at Action1, told the Express that if the victim is an administrator or a finance user, "the damage grows fast."
The US government is also treating it as urgent. On the same day, CISA added it to its Known Exploited Vulnerabilities catalog and gave federal agencies until November 24 to patch.
Summary: opening one crafted file in Outlook can leak your NTLMv2 hash with no warning. The rating is Moderate, but it's under active attack and listed by CISA.

The fix most people will miss: Outlook updates through Office​

The Express gives only the Windows Update steps. Those steps patch Windows, not Outlook. Microsoft has released fixes for Microsoft 365 Apps and Office LTSC 2021 and 2024. TheTechHacker puts it plainly: the fix doesn't come through Windows Update at all, it comes through Office's own updater, which a lot of people never look at.
Splashtop's prioritization guide also lists the zero-day fix as coming through the Microsoft 365 Apps and Office LTSC updates, on every device running Outlook, and recommends installing it within 72 hours.
Note that a Windows 11 laptop without classic Outlook or Office installed isn't exposed to this particular zero-day. It still needs the Windows fixes, though.

Step 1: Update Office (this fixes the zero-day)​

  1. Open Outlook, Word, or any other Office app.
  2. Go to File > Account.
  3. Choose Update Options > Update Now. TheTechHacker recommends updating Office first this way, because that's where the fix for CVE-2026-124194 is delivered.
  4. Let the update finish, then close and reopen Outlook.
What success looks like: Office reports that you're up to date after the check. If Update Now is missing or greyed out, your organization probably manages Office updates centrally, so ask IT whether the November build has been deployed.

Step 2: Update Windows 11​

  1. Click Start and open Settings.
  2. Select Windows Update.
  3. Click Check for updates, then Download and install if an update is waiting.
  4. Restart when prompted.
These are the November cumulative updates Microsoft lists for each Windows 11 version:
Windows 11 versionNovember 2026 update
26H2, 25H2, 24H2KB5132061
26H2, 25H2, 24H2 (hotpatch devices)KB5132043
26H1KB5132059
23H2KB5131087
Microsoft rates the Windows 11 family's highest severity this month as Critical, with remote code execution as the most serious impact. That's the worst case across all the Windows 11 fixes, not a description of the Outlook bug. Tenable highlights one of those Critical Windows fixes: CVE-2026-119952, an RCE vulnerability affecting Windows Schannel.
The Windows update isn't only about security, either. CyberInsider reports that it fixes USB audio, printer installation, and Remote Desktop problems while strengthening NTLM authentication and PowerShell script verification.
What success looks like: after the restart, Settings > Windows Update > Update history shows the KB number for your version as installed. To check your version, run winver.
Summary: update Office to fix the zero-day, then update Windows to fix everything else. One does not cover the other.

For admins: what to do first​

For managed environments, the security firms broadly agree on this order:
  • Outlook first. NTCompatible's advice: treat that 6.5 Outlook spoofing bug with the same urgency as a Critical RCE. Make sure your Microsoft 365 Apps channel or Office LTSC deployment has picked up the November build.
  • Identity systems next. Splashtop puts Active Directory Domain Services, LDAP, Schannel, and CredSSP on domain controllers and authentication servers in its 72-hour group. A stolen NTLM hash is most useful to an attacker when they can move from machine to machine.
  • Internet-facing servers. Exchange Server and IIS come next in the same guidance, starting with internet-facing systems. PDQ also flags CVE-2026-120002, a SharePoint Server elevation-of-privilege flaw scored 9.9 that requires no user interaction.
  • Reduce NTLM exposure. This is general industry practice rather than Microsoft guidance for this CVE: limiting outbound SMB/NTLM traffic to the internet at the perimeter has long been a defense against hash-leaking bugs like this one.
Microsoft's notice also says it updated 87 existing vulnerability records on November 10. Those changes were informational only and need no customer action, so they shouldn't be added to your patch queue. The next scheduled release is December 8, 2026 (US time).

Volume isn't the same as danger​

This is another very large month. Action1's Bicer told the Express it marks the third straight month of patch volumes that would have seemed extraordinary earlier in the year. He put October at 1,409 patches, the record. Other trackers count October differently: NTCompatible cites roughly 1,474. The exact number matters less than the trend.
Those totals can mislead in both directions. More than a thousand CVEs sounds alarming, but NTCompatible notes that only one flaw, the CVE-2026-124194 Outlook spoofing bug, was actually being exploited in the wild, and none were publicly disclosed before the patch. The Express warns "everyone with a Windows 11 laptop," but the danger this month comes from opening a file in Outlook, and owning a Windows 11 laptop doesn't put you at risk by itself.
So, should every Windows 11 user worry? No. Should every Windows 11 user who runs Outlook check Office updates today? Yes. Apart from that, the usual habits still apply: be wary of unexpected attachments, keep both updaters current, and restart when asked.
 
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