CVE-2024-4131
📋 TL;DR
A DLL hijack vulnerability in Lenovo Emulator allows local attackers to execute arbitrary code with elevated privileges by placing a malicious DLL in a location where the application searches for it. This affects users running vulnerable versions of Lenovo Emulator on Windows systems. Attackers need local access to the system to exploit this vulnerability.
💻 Affected Systems
- Lenovo Emulator
📦 What is this software?
Emulator by Lenovo
⚠️ Risk & Real-World Impact
Worst Case
Local attacker gains SYSTEM/administrator privileges, enabling complete system compromise, data theft, persistence installation, and lateral movement within the network.
Likely Case
Local attacker with standard user privileges escalates to administrator rights, allowing installation of malware, credential theft, and system configuration changes.
If Mitigated
Attack fails due to proper file permissions, application hardening, or security software blocking DLL loading from untrusted locations.
🎯 Exploit Status
DLL hijacking is a well-known attack technique; exploitation requires local access and ability to write to directories in the DLL search path.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not specified in reference; check Lenovo advisory for specific fixed version
Vendor Advisory: https://iknow.lenovo.com.cn/detail/423563
Restart Required: Yes
Instructions:
1. Visit Lenovo advisory URL. 2. Download and install the latest version of Lenovo Emulator. 3. Restart the system to ensure all processes use the patched version.
🔧 Temporary Workarounds
Restrict DLL search path permissions
windowsSet strict permissions on directories where Lenovo Emulator searches for DLLs to prevent unauthorized writes
icacls "C:\Program Files\Lenovo\Emulator" /deny Everyone:(OI)(CI)(W)
Use application control/whitelisting
windowsConfigure Windows Defender Application Control or third-party solutions to allow only signed DLLs to load
🧯 If You Can't Patch
- Remove or disable Lenovo Emulator if not required for operations
- Implement strict file system permissions to prevent DLL planting in application directories
🔍 How to Verify
Check if Vulnerable:
Check Lenovo Emulator version against patched version in Lenovo advisory; test by attempting to place a test DLL in application directory and observing if it loadsCheck Version:
Check application properties or registry: HKEY_LOCAL_MACHINE\SOFTWARE\Lenovo\EmulatorVerify Fix Applied:
Verify Lenovo Emulator version matches patched version; test that DLLs from untrusted locations no longer load📡 Detection & Monitoring
Log Indicators:
- Windows Event Logs: Process creation from unusual locations, DLL loading from non-standard paths
- Security logs: Unauthorized file writes to application directories
Network Indicators:
- Not applicable - local attack
SIEM Query:
EventID=4688 AND (NewProcessName contains "lenovo" OR NewProcessName contains "emulator") AND (CommandLine contains "dll" OR ParentProcessName contains unusual path)