CVE-2024-43491: Windows 10 1507 Privilege Escalation Flaw

CVE-2024-43491 Overview

Microsoft is aware of a vulnerability in the 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 updates until August 2024. All later versions of Windows 10 are not impacted by this vulnerability.

Critical Impact

Attackers can exploit previously mitigated vulnerabilities on affected systems, leading to potential control and data exposure.

Affected Products

• Microsoft Windows 10 1507

Discovery Timeline

• 2024-09-10 - CVE CVE-2024-43491 published to NVD
• 2024-09-26 - Last updated in NVD database

Technical Details for CVE-2024-43491

Vulnerability Analysis

This vulnerability affects the Windows 10 Servicing Stack, potentially rolling back prior security fixes. This can expose the system to known vulnerabilities, making it susceptible to attacks.

Root Cause

The root cause lies in the Servicing Stack's improper management of update rollbacks, which inadvertently reverts essential security patches.

Attack Vector

Network-based vector, as it can be exploited remotely over the network.

# PowerShell command example for illustrative purposes
(Get-HotFix | Where-Object { $_.HotFixID -eq "KB5035858" }).InstalledOn

Detection Methods for CVE-2024-43491

Indicators of Compromise

• Unexpected system instability
• Presence of old vulnerabilities
• Rollbacks on critical security patches

Detection Strategies

Utilize network traffic analysis to monitor for indicators of unauthorized access or anomalous behavior on affected systems.

Monitoring Recommendations

Regularly check system logs for any signs of rollback activity and use SentinelOne to automatically identify and remediate suspicious activities related to this vulnerability.

How to Mitigate CVE-2024-43491

Immediate Actions Required

• Install September 2024 Servicing Stack update (SSU KB5043936)
• Apply September 2024 Windows security update (KB5043083)
• Audit systems for existing vulnerabilities

Patch Information

Refer to the Microsoft Security Update Guide for detailed patching instructions and download links.

Workarounds

Consider applying temporary network isolation to vulnerable systems and use Endpoint Detection and Response tools to prevent exploitation.

# Example firewall rule to temporarily isolate affected systems
echo "Blocking inbound access to Services"
iptables -A INPUT -p tcp --dport 445 -j DROP