CVE-2024-30040
📋 TL;DR
CVE-2024-30040 is a security feature bypass vulnerability in the Windows MSHTML platform that could allow an attacker to circumvent security protections. This affects Windows systems where MSHTML is used for rendering web content, potentially enabling malicious code execution. Users running affected Windows versions are vulnerable.
💻 Affected Systems
- Microsoft Windows
📦 What is this software?
Windows 10 1507 by Microsoft
Windows 10 1607 by Microsoft
Windows 10 1607 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 21h2 by Microsoft
Windows 10 22h2 by Microsoft
Windows 11 21h2 by Microsoft
Windows 11 22h2 by Microsoft
Windows 11 23h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An attacker could bypass security features to execute arbitrary code with the privileges of the current user, potentially leading to full system compromise.
Likely Case
Attackers could bypass security controls to deliver malware or perform limited code execution in the context of the user's browser session.
If Mitigated
With proper security controls like application whitelisting and least privilege, impact is limited to the user's session without system-wide compromise.
🎯 Exploit Status
Microsoft has confirmed exploitation in the wild. Attack typically requires user interaction like opening a malicious document or visiting a compromised website.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: May 2024 security updates
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-30040
Restart Required: Yes
Instructions:
1. Apply May 2024 Windows security updates via Windows Update. 2. For enterprise: Deploy through WSUS or Microsoft Endpoint Configuration Manager. 3. Verify update installation and restart systems.
🔧 Temporary Workarounds
Disable IE Mode in Edge
windowsPrevents exploitation through Edge's IE mode by disabling this feature
Set Edge group policy: Configure Internet Explorer integration = Internet Explorer mode disabled
Restrict WebBrowser Control
windowsLimit applications using WebBrowser control through application control policies
🧯 If You Can't Patch
- Implement application control/whitelisting to prevent unauthorized code execution
- Use network segmentation to isolate vulnerable systems and restrict internet access
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for May 2024 security updates. If not installed and system is Windows 10/11 or Server 2019/2022, it's vulnerable.Check Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify KB5037768 (or later May 2024 cumulative update) is installed via 'winver' or 'systeminfo' command.📡 Detection & Monitoring
Log Indicators:
- Unusual MSHTML process activity
- Suspicious script execution from web content
- Security feature bypass events in Windows logs
Network Indicators:
- Unexpected outbound connections from browser processes
- Downloads of suspicious content to temporary locations
SIEM Query:
EventID=4688 AND (ProcessName="mshtml.dll" OR CommandLine CONTAINS "-Embedding") AND ParentProcessName IN ("iexplore.exe", "msedge.exe")