IRONSMITHINTEL
MEDIUMCVSS6.5
|
Actively Exploited
|CISA KEV|CVE-2024-43573|Auth: none — unauthenticated|Reboot: required|Manual only

KB5044273: Windows Server Security Update (October 2024)

Microsoft Windows MSHTML Platform contains an unspecified spoofing vulnerability which can lead to a loss of confidentiality.

Published Oct 8, 2024 · Updated May 16, 2026
Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve full data confidentiality loss. Federal agencies are required to remediate by 2024-10-29 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Cross-Site Scripting (XSS) (CWE-79) vulnerability in Microsoft Windows. Exploitation requires remote network access, low attack complexity, no authentication required, and user interaction required.

📧

Phishing link

→

🖼

Malicious file

🔓

Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

●Windows Administrators
●Systems Engineers
●IT Security
●Running windows 10 1507: v < 10.0.10240.20796; windows 10 1607: v < 10.0.14393.7428; windows 10 1809: v < 10.0.17763.6414; windows 10 21h2: v < 10.0.19044.5011; windows 10 22h2: v < 10.0.19045.5011; windows 11 21h2: v < 10.0.22000.3260; windows 11 22h2: v < 10.0.22621.4317; windows 11 23h2: v < 10.0.22631.4317; windows 11 24h2: v < 10.0.26100.2033; windows server 2012: r2; windows server 2016: v < 10.0.14393.7428; windows server 2019: v < 10.0.17763.6414; windows server 2022: v < 10.0.20348.2762; windows server 2022 23h2: v < 10.0.25398.1189
Fixed inKB5044273, KB5044277, KB5044280, KB5044281, KB5044284, KB5044285, KB5044286, KB5044288, KB5044293, KB5044343 (applies to 29 product versions) — build 10.0.10240.20796, 10.0.14393.7428+
Real-world incidentsWhat we've seen

CISA added this CVE to the Known Exploited Vulnerabilities catalog on 2024-10-08 based on evidence of active exploitation in the wild. Federal agencies required to remediate by 2024-10-29.

How to patch

Manual download

For air-gapped servers or out-of-band deployment. Microsoft Update Catalog returns every OS-version variant of this update.

↗ Microsoft Update CatalogKB5044273

Manual remediation steps

Apply the Microsoft Security Update

Microsoft has released an official security update that fixes this vulnerability.

Required KB Updates

    1
    KB5044273 — https://support.microsoft.com/help/5044273
    1
    KB5044277 — https://support.microsoft.com/help/5044277
    1
    KB5044280 — https://support.microsoft.com/help/5044280
    1
    KB5044281 — https://support.microsoft.com/help/5044281
    1
    KB5044284 — https://support.microsoft.com/help/5044284
    1
    KB5044285 — https://support.microsoft.com/help/5044285
    1
    KB5044286 — https://support.microsoft.com/help/5044286
    1
    KB5044288 — https://support.microsoft.com/help/5044288
    1
    KB5044293 — https://support.microsoft.com/help/5044293
    1
    KB5044343 — https://support.microsoft.com/help/5044343

Supersedes: KB5042881, KB5043050, KB5043051, KB5043055, KB5043064, KB5043067, KB5043076, KB5043080, KB5043083, KB5043138

Affected Products

    1
    Windows 10 Version 1607 for 32-bit Systems
    1
    Windows 10 Version 1607 for x64-based Systems
    1
    Windows 10 Version 1809 for 32-bit Systems
    1
    Windows 10 Version 1809 for x64-based Systems
    1
    Windows 10 Version 21H2 for 32-bit Systems
    1
    Windows 10 Version 21H2 for ARM64-based Systems
    1
    Windows 10 Version 21H2 for x64-based Systems
    1
    Windows 10 Version 22H2 for 32-bit Systems
    1
    Windows 10 Version 22H2 for ARM64-based Systems
    1
    Windows 10 Version 22H2 for x64-based Systems
    1
    Windows 10 for 32-bit Systems
    1
    Windows 10 for x64-based Systems
    1
    Windows 11 Version 22H2 for ARM64-based Systems
    1
    Windows 11 Version 22H2 for x64-based Systems
    1
    Windows 11 Version 23H2 for ARM64-based Systems
    1
    Windows 11 Version 23H2 for x64-based Systems
    1
    Windows 11 Version 24H2 for ARM64-based Systems
    1
    Windows 11 Version 24H2 for x64-based Systems
    1
    Windows 11 version 21H2 for ARM64-based Systems
    1
    Windows 11 version 21H2 for x64-based Systems
    1
    (…9 more product versions)

Fixed Build Numbers

    1
    10.0.10240.20796
    1
    10.0.14393.7428
    1
    10.0.17763.6414
    1
    10.0.19044.5011
    1
    10.0.19045.5011
    1
    10.0.20348.2762
    1
    10.0.22000.3260
    1
    10.0.22621.4317
    1
    10.0.22631.4317
    1
    10.0.25398.1189
    1
    (…2 more builds)

Installation Methods

Windows Update (recommended)

1
Settings → Windows Update → Check for updates
2
The security update is offered if your system is in scope
3
Restart when prompted — a reboot IS required to complete the install

Microsoft Update Catalog (manual download)

1
Open https://catalog.update.microsoft.com
2
Search for KB5044273
3
Download the package matching your OS architecture and Windows build
4
Run the .msu installer with administrator privileges
5
Restart when prompted

WSUS / SCCM / Intune

Approve KB5044273 for the affected products in your update management console.

Microsoft Download Center Links

    1
    https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5044273
    1
    https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5044277
    1
    https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5044280
    1
    https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5044281
    1
    https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5044284
    1
    (…5 more)

Verification

Confirm the update is installed:

Get-HotFix | Where-Object { $_.HotFixID -in @('KB5044273','KB5044277','KB5044280','KB5044281','KB5044284','KB5044285','KB5044286','KB5044288','KB5044293','KB5044343') }

References

    1
    Microsoft Security Response Center: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-43573
    1
    KB article: https://support.microsoft.com/help/5044273
    1
    KB article: https://support.microsoft.com/help/5044277
    1
    KB article: https://support.microsoft.com/help/5044280
    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2024-43573
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-43573
PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References

↗ CVE-2024-43573↗ MSRC Advisory↗ NVD↗ KBKB5044273