CVE-2024-43491: Microsoft Windows Update Use-After-Free Vulnerability
Microsoft is aware of a vulnerability in Servicing Stack that has rolled back the fixes for some vulnerabilities affecting Optional Components on Windows 10, version 1507 (initial version released July 2015). This means that an attacker could exploit these previously mitigated vulnerabilities on Windows 10, version 1507 (Windows 10 Enterprise 2015 LTSB and Windows 10 IoT Enterprise 2015 LTSB) systems that have installed the Windows security update released on March 12, 2024—KB5035858 (OS Build 10240.20526) or other updates released until August 2024. All later versions of Windows 10 are not impacted by this vulnerability. This servicing stack vulnerability is addressed by installing the September 2024 Servicing stack update (SSU KB5043936) AND the September 2024 Windows security update (KB5043083), in that order. Note: Windows 10, version 1507 reached the end of support (EOS) on May 9, 2017 for devices running the Pro, Home, Enterprise, Education, and Enterprise IoT editions. Only Windows 10 Enterprise 2015 LTSB and Windows 10 IoT Enterprise 2015 LTSB editions are still under support.
Other sources
Microsoft Windows Update contains a use-after-free vulnerability that allows for remote code execution.
— CISA
Microsoft Windows Update Remote Code Execution Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.10240.20766Patch KB5043083 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch KB5043936 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch KB5043083 - Operational
Apply the September 2024 Servicing stack update (SSU KB5043936) and then the September 2024 Windows security update (KB5043083), in that order, on Windows 10 version 1507 (Windows 10 Enterprise 2015 LTSB and Windows 10 IoT Enterprise 2015 LTSB).
Event History
Frequently Asked Questions
What is the severity of CVE-2024-43491?
CVE-2024-43491 is considered a critical vulnerability due to its ability to allow remote exploitation of previously mitigated vulnerabilities.
How do I fix CVE-2024-43491?
To fix CVE-2024-43491, ensure that your Windows 10 system is updated with the latest patches provided by Microsoft, particularly KB5043083.
What versions of Windows are affected by CVE-2024-43491?
CVE-2024-43491 specifically affects Windows 10, version 1507, which was initially released in July 2015.
Can CVE-2024-43491 be exploited by attackers?
Yes, CVE-2024-43491 can be exploited by attackers due to the rollback of previously applied fixes for vulnerabilities in Optional Components.
Is there a known workaround for CVE-2024-43491?
There are no official workarounds for CVE-2024-43491, and the recommended solution is to apply available updates immediately.