CVE-2025-12852
📋 TL;DR
This DLL loading vulnerability in NEC RakurakuMusen Start EX allows attackers to manipulate the PC environment to execute arbitrary code by placing malicious DLLs in specific locations. All users of this NEC software are affected.
💻 Affected Systems
- NEC Corporation RakurakuMusen Start EX
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with remote code execution, data theft, and persistent backdoor installation
Likely Case
Local privilege escalation leading to unauthorized system access and data manipulation
If Mitigated
Limited impact if proper file permissions and execution controls prevent DLL planting
🎯 Exploit Status
Requires ability to place malicious DLL in specific directory paths
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to latest version as specified in NEC advisory
Vendor Advisory: https://jpn.nec.com/security-info/secinfo/nv25-007_en.html
Restart Required: Yes
Instructions:
1. Visit NEC security advisory page
2. Download latest version of RakurakuMusen Start EX
3. Install update following vendor instructions
4. Restart system
🔧 Temporary Workarounds
Restrict DLL loading paths
windowsConfigure Windows to prevent loading DLLs from untrusted directories
Set SafeDllSearchMode registry key to 1
Configure DLL search order via group policy
File permission hardening
windowsRestrict write permissions to application directories
icacls "C:\Program Files\NEC\RakurakuMusen" /deny Users:(OI)(CI)W
🧯 If You Can't Patch
- Remove or disable RakurakuMusen Start EX software
- Implement application whitelisting to block unauthorized DLL execution
🔍 How to Verify
Check if Vulnerable:
Check if RakurakuMusen Start EX is installed and version matches affected rangeCheck Version:
Check program properties or NEC software information panelVerify Fix Applied:
Verify software version matches patched version from NEC advisory📡 Detection & Monitoring
Log Indicators:
- Unexpected DLL loading from unusual directories
- Process creation from RakurakuMusen with suspicious parent processes
Network Indicators:
- Unusual outbound connections from RakurakuMusen process
SIEM Query:
Process Creation where Image contains 'RakurakuMusen' and CommandLine contains 'dll'